last night, lynn spent 1 1/6 h writing her english composition and 1 3/10 h working on her math...
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Last night, Lynn spent 1 1/6 h writing her English composition and 1 3/10 h working on her Math worksheets. How much time did she spend on her homework altogether?
6
11
10
31
6
11
10
31+
30
52
30
9+=
30
142=
15
72=
Fractions, Word Problems
Example 1
English Math
Total Time = Time for English + Time for Math
= h
Ali planned to complete his homework in 1 ½ h. He finished his homework in 1 1/3 h instead. How much less time did he take to finish his homework?
2
11
3
11
2
11
3
11-
6
3=
6
1=
6
2-
?
Fractions, Word Problems
Example 2
Planned Actual
Less Time = Planned Time - Actual Time
Less Time
= h
ActualPlanned
Subtract the actual time from planned
time.It took him
lesser amount of time to finish his homework than what was
planned.
Ali planned to complete his homework in 1 ½ h. He finished his homework in 1 1/3 h instead. How much less time did he take to finish his homework?
2
11
3
11
2
11
3
11-
6
3=
6
1=
6
2-
?
Fractions, Word Problems
Example 2 (Variation)
Planned Actual
Less = Planned Time - Time Actual Time
Less Time
=
h
Actual
Planned
Bala had 2 similar loaves of bread. He used ¾ of a loaf of bread to make sardine sandwiches. He used 1/2 of a loaf of bread to make egg sandwiches.
4
3
4
11
2
1= 4
3
4
2=4
5=
Egg
2
1
4
3
Total
Loaves Used ?
=
Sardine
Fractions, Word Problems Example 3
a. How many loaves of bread did Bala use altogether?
Bala had 2 similar loaves of bread. He used ¾ of a loaf of bread to make sardine sandwiches. He used 1/2 of a loaf of bread to make egg sandwiches.
4
3
2
1= 4
3
4
2=4
1
Difference
? =
Fractions, Word Problems Example 3
Egg
2
1
4
3
Sardine
b. How much more bread did he use to make sardine sandwiches than egg sandwiches?
Gina used 3/8 kg of butter to make buns and ½ kg of butter to make cream puffs. She had 1/8 kg of butter left.
8
3
2
1= 8
3
8
4= kg8
7
BunsCream Puffs
8
3
2
1
Total Used
? =
Fractions, Word Problems
Example 4
a. How much butter did Gina use altogether?
Gina used 3/8 kg of butter to make buns and ½ kg of butter to make cream puffs. She had 1/8 kg of butter left.
b. How much butter did she have at first?
8
7
8
1=8
8= kg1
8
7
Total Used
At first
8
18
7
=
Fractions, Word Problems
Example 4
Amount of butter left.
David had 2 similar loaves of bread. After making some sandwiches, he had 2/3 of a loaf of bread left. How many loaves of bread did David use?
1 loaf of bread
1 loaf of bread
Fractions, Word Problems
Example 5
?Amount of bread
used.
23
11
3
2= 3
31
3
2==
Amount of bread left.
Means divide I loaf into 3 parts and take 2
parts
3
2
Mrs. Chen has 9 stalks of roses. 6 of them are red. The rest are yellow.
Fractions, Word Problems
Example 6
a. What fraction of the roses are red?
b. What fraction of the roses are yellow?
You should know the total number of
roses
and the number of red roses.9
6
3
2or
You should know the total number of
rosesand the number of yellow roses.9
3
3
1or
Six out of nine roses
are red.
Three out of nine roses are yellow.
a. What fraction of the class are girls?
6
2
2 out of 6 are girls.
Two sixths are girls.
Fractions, Word Problems
Example 7
There are 6 pupils in a class. 2 of them are girls.
b. What fraction of the class are boys?
6
4
4 out of 6 are boys.
Four sixths are boys.
Fractions, Word Problems
Example 7
There are 6 pupils in a class. 2 of them are girls.
Shanti had ¾ kg of cheese. She used 2/3 of the cheese to bake a cake. What was the mass of cheese she used?
12
Fractions, Word Problems
Example 8
12 g
= Amount of cheese used.
= ? g
Means divide the cheese into 3 parts and take 2 parts.
3
2
Shanti had ¾ kg of cheese. She used 2/3 of the cheese to bake a cake. What was the mass of cheese left?
3
2=
1
12
3
2x =
3
24= g8
12
of 12 g
Fractions, Word Problems
Example 8
= Amount of cheese used.
= ? g3
2
12 g
Shanti had ¾ kg of cheese. She used 2/3 of the cheese to bake a cake. What was the mass of cheese left?
12
Fractions, Word Problems
Example 8
= Amount of cheese used.3
2Amount of cheese left.?
What fraction of the
cheese left?
12 g
Shanti had ¾ kg of cheese. She used 2/3 of the cheese to bake a cake. What was the mass of cheese left?
3
1=
1
12
3
1x =
3
12= g4
12
of 12 g
Fractions, Word Problems
Example 8
= Amount of cheese used.3
2Amount of cheese left.?
What fraction of the
cheese left?
12 g
Shanti had ¾ g of cheese. She used 2/3 of the cheese to bake a cake. What was the mass of cheese left?
Fractions, Word Problems
Example 8 (variation)
Amount of cheese used.
g4
3
3
1=
4
3
3
1x = g
4
1of g4
3
Amount of cheese left.?
Instead of 12 g from our last example.
What fraction of the
cheese left?
You should know the
methods used in getting fraction
of a set.
A tank can hold 35 l of water. Some water was poured out and is now 2/5 full.
Fractions, Word Problems
Example 8
35 l
? ? Amount of
water poured.
How much water has been poured from the tank?
Means divide the container into 5 parts and take 2 parts.
Amount of water left.? 5
2
What fraction of the water
poured?
A tank can hold 35 l of water. Some water was poured out and is now 2/5 full.
Fractions, Word Problems
Example 8
35 l
? ? Amount of
water poured.
How much water has been poured from the tank?
Amount of water left. 5
2
What fraction of the water
poured?
5
3= = 21of l35 l
1
35
5
3x
There are 36 pupils in a class. 1/3 of the pupils wear glasses.
3
2= 24of pupils36
36
Fractions, Word Problems
Example 9
Wear glasses.
?
= 363
2x
Means divide the class into 3 parts and take 1 part.
?
How many pupils do not wear glasses?
3
1 ? Don’t wear
glasses.
What fraction of the pupils don’t wear glasses?
pupils
How many
wear glasses?
12pupils
Don’t wear glasses.
How did you get
12?
- 24 pupils
There are 36 pupils in a class. 1/3 of the pupils wear glasses.
3
1of pupils36
36
Fractions, Word Problems
Example 9
Wear glasses.
?
= 363
1x
How many pupils do not wear glasses?
3
1 ? Don’t wear
glasses.
How many
wear glasses?
12pupils
How did you get
12?
There are 30 girls in a class. 2/3 of the pupils in the class are girls. How many pupils are boys?
Fractions, Word Problems
Example 10
boys girls 2 units = 30
1 unit = 15
The girls are 2 parts of 3
parts.The class is
divided into 3 parts.
class
30 girls? boys
151515
There are 15 boys in the classThere are 15 boys in the class.
? girls
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