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Green
Book 11
The wee Maths
Book of Big
Brain
Growth
Expressions and Formulae, Patterns and
Gradient
Grow your brain
Guaranteed to make
your brain grow, just
add some effort and
hard work
Don’t be afraid if
you don’t know how
to do it, yet!
It’s not how fast you
finish, but that you
finish.
It’s always better to
try something than
to try nothing.
Don’t be worried
about getting it
wrong, getting it
wrong is just part of
the process known
better as learning.
Page | 2
Expressions and Formulae
N31 I can use algebraic shorthand and gather like terms.
1. Ben was thinking of a number, the last
digit of the password for the laptop, and
Eva hasn’t been told what it is.
At this point, as far as Eva is concerned,
the number can be anything from zero to
nine.
It is unknown and variable.
Eva says to Ben, I’m going to call the
number 𝑃 just like we did in Maths when
you were off with the flu.
(a) Ben says he will tell Eva what double the number is, so Eva wrote
down an expression for this in algebraic shorthand.
Write down, in algebraic shorthand, an expression for double the
variable 𝑃.
(b) Ben changes his mind and says he will tell Eva the answer to five
times the number.
Write down, in algebraic shorthand, an expression for five times
the variable 𝑃.
(c) In your own words write down what you think 7𝑃 means.
(d) Ben eventually writes this down for Eva
10𝑃 = 60
What is the last digit of the password?
Page | 3
2. Ben missed some lessons on algebra, so he has asked Eva to help him.
Eva says that 5𝑝 is an expression which means 5 groups of an
unknown, or variable, number 𝑝.
She also says that if we add a known, or constant, number to 𝑥 we
can also show this in the expression.
Eva showed Ben this note in her jotter
Complete the following which Eva used to test Ben’s understanding.
(a) Write down an expression for five groups of a variable number 𝑥.
(b) Write down an expression for 7 groups of the unknown number 𝑡.
(c) Write down an expression for 6 groups of the variable number 𝑎
plus the constant 10.
(d) Write down an expression for 2 groups of the variable 𝑝 plus 3
groups of the variable 𝑞.
(e) Write down an expression for 5 groups of the variable number 𝑟
plus the constant 8.
(f) Write down an expression for 4 groups of the variable 𝑢 plus 3
groups of the variable 𝑣.
Page | 4
3. Write down an expression which
contains two different variables.
4. Write down an expression which
contains one variable and one
constant.
5. Write down an expression which contains three different variables.
6. Write down an expression which contains one unknown and a one
constant.
7. Rewrite each of the following products without the multiplication
sign.
(a) 4×𝑝 (b) 10×𝑦 (c) 𝑝×3 (d) 𝑧×5
(e) 𝑝×𝑞 (f) 𝑏×𝑐×𝑑 (g) 5×𝑟×𝑠 (h) 𝑝×𝑝
8. Simplify each of the following expressions.
(a) 4𝑦 + 3𝑦 (b) 5𝑝 + 5𝑝 (c) 3𝑥 + 𝑥
(d) 6𝑦 − 2𝑦 (e) 5𝑑 − 𝑑 (f) 4𝑝 + 2𝑞
9. Simplify each of the following expressions.
(a) 2𝑝 + 5𝑝 + 3𝑞 + 4𝑞 (b) 6𝑦 + 7𝑦 + 4𝑣 + 5𝑣
(c) 6𝑥 − 2𝑥 + 3𝑦 + 4𝑦 (d) 8𝑐 − 3𝑐 + 5𝑑 − 𝑑
(e) 5𝑥 + 2𝑥 + 4 + 3 (f) 8𝑦 − 𝑦 + 7 − 4
(g) 3𝑥 + 2𝑦 + 2𝑥 + 5𝑦 (h) 6𝑥 + 7 + 5𝑥 + 3
Page | 5
10. Write these out in algebraic shorthand
(a) 𝑥 + 𝑥 + 𝑥 + 𝑥 + 𝑥 + 𝑥 (b) 𝑎 + 𝑎 + 𝑎 + 𝑎 + 𝑎
(c) 𝑝 + 𝑝 + 𝑝 + 𝑝 + 𝑝 + 𝑝 (d) 𝑡 + 𝑡 + 𝑡 + 𝑡
(e) 𝑟 + 𝑟 + 𝑟 + 𝑟 + 𝑟 + 𝑟 + 𝑟 (f) 3×𝑥
(g) 5×𝑝 (h) 7×𝑟
(i) 8×𝑡 (j) 4×𝑎
11. Gather up these like terms
(a) 5𝑥 + 3𝑥 (b) 6𝑟 + 2𝑟 (c) 5𝑝 + 12𝑝
(d) 4𝑡 + 𝑡 (e) 𝑠 + 12𝑠 (f) 9𝑥 − 5𝑥
(g) 35𝑟 − 13𝑟 (h) 19𝑝 − 11𝑝 (i) 44𝑠 − 33𝑠
(j) 5𝑡 − 5𝑡 (k) 12𝑠 − 3 + 7𝑠 (l) 12𝑟 + 3𝑟 + 12
(m) 7𝑥 − 4𝑥 + 9 (n) 𝑠 + 8 − 𝑠 (o) 4𝑡 + 9 + 𝑡
(p) 11 + 2𝑝 − 𝑝 (q) 4𝑟 + 6𝑟 − 2 (r) 4𝑡 + 9𝑦 − 𝑡
(s) 9𝑠 + 6𝑡 − 7𝑠 (t) 12𝑝 − 3 − 5𝑝 (u) 2𝑥 + 3 − 2𝑥 + 9
12. Simplify by gathering like terms
(a) 3𝑥 + 5𝑥 + 2𝑦 + 8𝑦 (b) 4𝑠 + 3𝑠 + 7𝑡 + 8𝑡
(c) 4𝑝 + 9𝑝 + 3𝑝 + 6𝑝 (d) 7𝑢 + 5𝑢 + 3𝑣 + 6𝑣
(e) 5𝑥 − 2𝑥 + 6𝑦 + 7𝑦 (f) 9𝑝 − 3𝑝 + 8𝑞 − 3𝑞
(g) 4𝑥 + 3𝑥 + 7 + 9 (h) 9𝑦 − 2𝑦 + 8 − 3
(i) 4𝑥 + 3𝑦 + 6𝑥 + 2𝑦 (j) 5𝑥 + 7 + 8𝑥 + 1
(k) 5𝑥 + 3𝑦 − 3𝑥 − 2𝑦 (l) 7𝑥 + 12 + 3𝑥 − 1
Page | 6
13. Eva asked Ben to simplify 7𝑥 + 3 − 4𝑥 by gathering like terms.
Ben’s working is shown below.
(a) Can you spot Ben’s mistake?
Write out the correct solution showing all working.
(b) What advice would you give Ben so that he could learn from this
mistake?
14. Define a variable and write down expressions to illustrate the
following.
(a) Eva is a baker and bakes some cakes. Each cake needs 3 eggs.
How many eggs did she use?
(b) Ben caught 10 fish and gave some to Morven.
How many fish does Ben have left?
(c) Cara has some money and is going to share it equally amongst
five charities.
How much will each charity get?
(d) Mark had some plectrums for his guitar but then bought four
more.
How many plectrums does Mark now have?
Page | 7
N32 I can use the Distributive Law to multiply out brackets and
gather Like Terms
15. Expand the brackets:
(a) 2(4𝑎 − 3) (b) 6(4𝑦 + 3) (c) 3(2𝑥 − 5)
(d) 4(5𝑐 + 6) (e) 7(2𝑎 + 1) (f) 2(8𝑥 + 3)
(g) 5(6𝑥 − 7𝑦) (h) 3(8𝑡 5𝑢) (i) 3(9𝑥 − 4𝑦)
(j) 8(7𝑥 + 5𝑦) (k) 7(2𝑏 + 9𝑐) (l) 2(12𝑥 + 7𝑦)
16. Expand and simplify:
(a) 2𝑎 + 3(𝑎 + 5) (b) 3𝑥 + 2(𝑥 + 3)
(c) 4𝑏 + 8(𝑏 + 2) (d) 5ℎ + 4(2ℎ + 1)
(e) 11𝑥 + 5(3𝑥 + 4) (f) 10𝑐 + 3(2𝑐 + 1)
(g) 2(4𝑡 + 3) + 10𝑡 (h) 3(5𝑝 + 4) + 7𝑝
(i) 7(1 + 3𝑐) + 10 (j) 3(3𝑎 1) + 2𝑎
(k) 2(5𝑥 + 3) − 3𝑥 (l) 8(𝑏 + 2) − 9
17. Expand and simplify:
(a) 6 + 2(𝑎 + 7) (b) 10 + 2(𝑥 + 3)
18. Expand and simplify:
(a) 2(𝑎 + 1) + 7(𝑎 + 3) (b) 3(𝑥 + 2) + 3(𝑥 + 1)
(c) 5(𝑏 + 3) + 2(𝑏 − 1) (d) 2(ℎ + 9) + 3(2ℎ − 1)
(e) 7(𝑥 + 5𝑦) + 2(3𝑥 + 2𝑦) (f) 6(𝑐 + 5𝑑) + 4(𝑐 + 2𝑑)
Page | 8
N33 I can use the correct order of operations (BODMAS).
19. Evaluate the following
(a) 2×3 + 5×4 (b) 6 − 2×2 (c) 3 + 20 ÷ 4
(d) 3×(5 + 1) (e) 30
5− (4 + 2) (f) (3 + 2)×(6 − 4)
20. Evaluate the following
(a) 15 ÷ 3 + 6×2 − 10 (b) 8×3 + 12×2 − 1
(c) 7×3 + 3 − 2×4 (d) 10×2 + 3 − 4 ÷ 2
21. Evaluate the following
(a) 3+9
6 (b)
6+12
5−1 (c)
4×(6−1)
18−4×2
22. In each of the examples below, spot the mistake and write out the
correct solution.
(a) 3 + 4×(5 − 3) (b) 5 − 2×2
= 7×2 = 3×2
= 14 = 6
(c) 6×3 − 4×3 (d) 8 ÷ 2 + 5×2
= 18 − 4×3 = 4 + 5×2
= 14×3 = 9×2
= 42 = 18
Page | 9
N34 Evaluating an expression or a formula which may include
more than one variable.
23. Evaluate the following expressions
(a) 𝑥 + 𝑦 when 𝑥 = 5 and 𝑦 = 3.
(b) 𝑎 + 4 when 𝑎 = 7.
(c) 5𝑥 when 𝑥 = 8.
(d) 3𝑦 when 𝑦 = 12.
24. Evaluate the following expressions
(a) 𝑡 − 𝑠 when 𝑡 = 8 and 𝑠 = 3.
(b) 17 − 𝑏 when 𝑏 = 9.
(c) 3𝑎 + 2𝑏 when 𝑎 = 7 and 𝑏 = 5.
(d) 4𝑥 + 3𝑦 when 𝑥 = 9 and 𝑦 = 2.
25. Evaluate the following expressions
(a) 7𝑝 + 5𝑞 when 𝑝 = 1 and 𝑞 = 3.
(b) 8𝑠 + 6𝑡 when 𝑠 = 0 and 𝑡 = 8.
(c) 𝑎
𝑏 when 𝑎 = 12 and 𝑏 = 3.
26. Evaluate the following expressions
(a) 48
𝑏 when 𝑏 = 6. (b)
3𝑟
𝑠 when 𝑟 = 8 and 𝑠 = 4.
Page | 10
27. The cost of hiring a taxi can be found using the formula
𝑐 = 2𝑑 + 1
Where 𝑐 is the cost of the hire in pounds and 𝑑 is the distance
travelled in miles.
(a) Use the formula to find the cost of a 3 mile hire.
(b) John is charged £11 for a 5 mile journey.
Was John charged the correct fee?
Use a calculation, involving the formula, to justify your answer.
28. The perimeter of a rectangle can
be found using the formula
𝑃 = 2𝑙 + 2𝑏
Where 𝑃 is the perimeter, 𝑙 is the length of the rectangle and 𝑏 is
the breadth of the rectangle.
(a) Use the formula to find the perimeter of a rectangle of length 14
cm and breadth 8 cm.
(b) Does a rectangle with breath 5m and length 7m have a perimeter
of 22m?
Use a calculation, involving the formula, to justify your
answer.
Page | 11
N35 I can factorise expressions using common factor
29. Factorise each of the following expressions.
Always check your answer by “multiplying out”.
(a) 3𝑥 + 27 (b) 10𝑒 – 50𝑘 (c) 30 – 5𝑏
(d) 16𝑐 + 4𝑟 (e) 4𝑝 – 6 (f) 6𝑔 + 9𝑎
(g) 25 + 10𝑑 (h) 28𝑘 – 16𝑚 (i) 8𝑡 + 16
30. Factorise each of the following expressions
Always check your answer by “multiplying out”.
(a) 𝑝𝑞 + 4𝑝 (b) 5𝑎𝑏 – 2𝑏𝑑 (c) 10𝑔ℎ + 3ℎ
(d) 𝑥𝑦 – 2𝑦 (e) 8𝑡𝑣 + 7𝑡 (f) 𝑚𝑛 – 6𝑚
(g) 5𝑒𝑔 + 𝑔 (h) 9𝑠𝑡 – 11𝑠 (i) 8𝑝𝑡 + 16𝑡
31. Factorise each of the following expressions
Always check your answer by “multiplying out”.
(a) 7𝑥𝑦 + 21𝑥 (b) 16𝑎𝑏 – 12𝑏 (c) 10𝑚 + 25𝑚𝑛
(d) 30𝑔 + 2𝑔ℎ (e) 6𝑠𝑡 – 27𝑠 (f) 8𝑝𝑞𝑟 + 32𝑞𝑟𝑠
(g) 12𝑏𝑧 + 18𝑏𝑞 (h) 30𝑣𝑤 – 20𝑒𝑤 (i) 4𝑝𝑡 + 12𝑝𝑟
Page | 12
Patterns
N36 I can extend a straightforward sequence.
1. List the next five terms in each sequence.
(a) 5, 10, 15, 20, …… (b) 40, 37, 34, 31, ……….
(c) 1, 2, 4, 8, 16, …… (d) 4, 9, 16, 25, ……….
(e) 1, 3, 6, 10, …… (f) 0, 1, 1, 2, 3, 5, ……….
2. List the next two terms in each sequence.
(a) 512, 256, 128, 64, 32, ….. (b) 10, 13, 16, 19, 22, 25, , ,
(c) 129, 116, 103, 90, 77, ….. (d) 101, 90, 79, 68, 57, 46, , ,
(e) 2, 4, 8, 16, 32, 64,….. (f) 34, 31, 28, 25, 22, 19, , ,
(g) 7, 7, 10, 13, 13, 16,….. (h) 21, 19, 17, 15, 13, 11, , ,
3. The first 5 terms of some sequences are shown below.
In each case what is the value of the twentieth term.
(a) 4, 8, 12, 16, 20 ………. (b) 1, 3, 5, 7, 9 ……….
(c) 4, 9, 14, 19, 24, ………. (d) 3, 7, 11, 15, 19 ……….
(e) 1, 4, 9, 16, 25 ………. (f) 1, 1, 2, 3, 5, ……….
Page | 13
Pattern 1 Pattern 2 Pattern 3
N37 I can extend a pattern in diagram format.
4. Draw the next two patterns in the sequence of dots below.
5. Draw the next two patterns in this sequence of dots.
6. Draw the next two patterns in the sequence of dots and squares
below.
Page | 14
N38 I can complete a table from a pattern or formula.
7. A pattern, using matchsticks to make triangle, is shown below.
(a) Draw the next set of triangles in the sequence.
(b) Copy and complete the table below:
8. Look at the pattern of trapezium shaped tables and customers in a
restaurant.
(a) Draw the next set of tables in the sequence.
(b) Copy and complete the table below:
No. of Triangles 1 2 3 4 5 6
No. of Matchsticks 3 5
No. of Tables 1 2 3 4 5 6
No. of customers
Page | 15
N39 I can find a formula for a linear Patterns and can evaluate
the formula for a given value.
9. The diagrams below show the number of people sitting at desks.
(a) Draw the next diagram in the sequence.
(b) Copy and complete the table below for this pattern.
Number of Desks (𝑑) 1 2 3 4 5 6
Number of People (𝑝) 4 6
(c) Write down a formula connecting 𝑝 and 𝑑.
(d) Use the formula to find the number of people who can be sat at:
(i) 35 desks. (ii) 78 desks. (iii) 105 desks.
(e) How many desks would be needed for 78 people?
Page | 16
10. A manufacturer makes necklaces in various sizes.
(a) Draw the next size in the sequence.
(b) Complete this table to show how the pattern is built up.
Number of Rings (𝑟) 1 2 3 4 5 6
Number of Beads (𝑏) 4 7
(c) Write down a formula connecting 𝑏 and 𝑟.
(d) Use the formula to find the number of beads needed for:
(i) 24 rings. (ii) 54 rings. (iii) 98 rings.
(e) How many rings can be made from 76 beads.
2 rings 7 beads 1 ring 4 beads
Page | 17
Pattern 1 Pattern 2 Pattern 3
11. These patterns are made with circles.
(a) Draw pattern 4.
(b) Copy and complete the table below.
Pattern Number (𝑃) 1 2 3 4 5 6
Number of Circles (𝑐) 1 4
(c) Write down a formula connecting 𝑐 and 𝑃.
(d) Use the formula to find the number of circles in:
(i) Pattern 12. (ii) Pattern 45. (iii) Pattern 86.
(e) What pattern number would contain 28 circles?
Page | 18
12. A design consists of rectangles and triangles.
The first three patterns are shown.
(a) Draw the 4th Pattern.
(b) Copy and complete the table below.
(c) Write down a formula connecting 𝑡 and 𝑟.
(d) Use the formula to find the number of triangles in a pattern with:
(i) 33 rectangles. (ii) 75 rectangles. (iii) 112 rectangles.
(e) How many rectangles in a pattern with 42 triangles?
Number of Rectangles (𝑟) 1 2 3 4 5 6
Number of Triangles (𝑡) 6 8
Page | 19
13. Fences are built using posts and boards as shown below.
(a) Draw the next fence in the sequence.
(b) To help plan how many boards are needed to build a fence copy
and complete the table below:
(c) Write down a formula connecting 𝐵 and 𝑝.
(d) Use the formula to find the number of boards required for:
(i) 47 posts. (ii) 86 posts. (iii) 150 posts.
(e) How many posts are required for a fence with 106 boards?
No. of Posts (𝑝) 2 3 4 5 6 7 15
Number of Boards (𝐵) 4 7
Page | 20
Gradient
M12 I can calculate the gradient of a slope
1. Express each fraction in its simplest form, as a ratio, a decimal and a
percentage
(a) 5
10 (b)
3
9 (c)
2
8 (d)
10
2
(e) 6
9 (f)
8
12 (g)
15
20 (h)
30
20
(I) 14
35 (j)
16
12 (k)
24
40 (l)
50
42
For each of the following diagrams, find the gradient and give your answer
as a fraction in its simplest form, as a ratio, as a decimal fraction and as a
percentage.
Example: 2
5= 2: 5 (or 2 in 5) = 0 ∙ 4 = 40%
2. 3.
12m
3m
35cm
7cm
Page | 22
M13 I can communicate a decision which involved gradient.
10. The cross section of a doorstep is shown below.
(a) Calculate the vertical height, ℎ.
(b) A satisfactory doorstop has a gradient less than 0∙3. Is the
doorstop shown satisfactory?
Give a reason for your answer
11. A mountain railway tunnel
rises 150m over a horizontal
distance of 500m.
(a) Calculate the gradient of the railway line going through the
tunnel.
(b) The rail company are investing in new trains.
The new trains cannot operate if the gradient is greater
than 0∙15.
Will the new trains be able to operate through the tunnel?
Give a reason for your answer
22cm
20cm ℎ
500m
150m
Page | 23
12. A new regulation states that the gradient of all ramps into a building
must be less than 0∙26.
An existing ramp is 410cm long and has a horizontal distance of
400cm.
Does this ramp satisfy the new regulation?
Show all your working and give a reason for your answer.
13. To meet safety regulations, the gradient of a children’s slide must be
between 2
5 and
3
4.
A company designs the slide shown.
Does this slide fit the safety regulations?
Use your working to explain your answer.
5m
530cm