Using Mathematics to Solve Everyday Problems

Lesson 3 & 4

TEKS 6.11A/B

Follow these steps when solving problems:

• Understand the Problem. Organize the information and identify exactly what you must find. Information that is not given in the problem, such as a formula, may be needed. Information that is not needed in order to solve the problem may be given.

• Make a plan. Decide how to use this information to find an answer. Think about the math concepts that apply to the situation. Identify the order in which to find new information and the formulas or equations to be used to find an answer.

• Carry out the plan. After choosing a problem-solving strategy, use the strategy to work toward a solution to the problem. Go step-by-step through the plan, writing down important information at each step.

• Check to see whether the answer is reasonable. Check to see whether the answer makes sense. Does it answer the question asked? Is it stated in the correct units? Is it reasonable?

EX 1:• One string on a musical instrument

vibrates at a constant rate of 196 vibrations each second. At this rate, how many times does the string vibrate in 45 seconds?

Understand• What do you know?

– One string on a musical instrument vibrates at a constant rate of 196 vibrations each second.

One string on a musical instrument vibrates at a constant rate of 196 vibrations each second. At this rate, how many times does the string vibrate in 45 seconds?

• What do you want to know?– How many times the string vibrates in 45

seconds?

• Plan– How do you find number of times the string

vibrates in 45 seconds?• Multiply the number of times the string vibrates

each second by the number of seconds to find the number of times the string vibrates in 45 seconds.

One string on a musical instrument vibrates at a constant rate of 196 vibrations each second. At this rate, how many times does the string vibrate in 45 seconds?

• Solve– 196 x 45 = v– V = 8,820

• Look Back– 196 rounds to 200– 200 x 45 = 9,000

Ex 2:

Carmella is planning a budget for her clothes for her family vacation. She is saving $25 per week. So far she has saved $125. She plans to spend about $200 on clothes for the vacation. She is planning to purchase items that range in price from $2 to $50. Will Carmella have enough money for her clothes for vacation?

Carmella is planning a budget for her clothes for her family vacation. She is saving $25 per week. So far she has saved $125. She plans to spend about $200 on clothes for the vacation. She is planning to purchase items that range in price from $2 to $50. Will Carmella have enough money for her clothes for vacation?

Understand

• What do you know?

1. Camella saves $25 per week.

2.She has already saved $125.

3.She plans to spend $200 on clothes for her vacation.

Carmella is planning a budget for her clothes for her family vacation. She is saving $25 per week. So far she has saved $125. She plans to spend about $200 on clothes for the vacation. She is planning to purchase items that range in price from $2 to $50. Will Carmella have enough money for her clothes for vacation?

• What do you want to know?– Will Carmella have enough money for

her vacation clothes?

• Do we have enough information?– We don’t know when she will go

shopping.– We don’t know how many weeks she

has left to save.

• No we need more information