Writing Equivalent Expressions (Summative)

Name:_Answer Key______Date:______Translate each verbal phrase into a number sentence.

1. Three less the product of seven and a number h.

7h - 3

2. Three times the quantity ten minus r.

3 (10 – r)

3. Stan and Marsha each earn an hourly wage of $10 per hour. This week, Marsha received an additional bonus of $50. They both worked the same number of hours. The following expression represents the weekly wages they earned altogether: h ($10) + h ($10) + $50

a) Explain what each of the following represents in this situation. h ($10): h represents the number of hours Stan worked and the $10 is what he was paid for each of those hours so the expression represents what Stan earned

+ h($10): same as above except this is for Marsha’s hours. You add the two quantities because the question is what they made altogether

$50 this is the bonus money that Marsha made

b) h($20) + $50 also represents the wages they earned altogether. Explain what each of the following represents in this situation. h($20): Stan and Marsha worked the same number of hours so h represents these hours. Each earned $10 per hour so the $20 represents what they both earned each hour.

+ $50 This is the bonus money Marsha earned. 4. The temperature in Iceland increases 2 degrees in the morning but then falls 7 degrees by midnight for the next 5 days. Write two equivalent expressions to determine the temperature at the end of the 5 days (midnight).

Possible Solutions: T + 5 (2-7) ; T – 5(5); T + 5(-5)

5. The length of one side of a square is 12 + x.

a. Using only addition, write an expression to find the perimeter of the square.

12 + x + 12 + x + 12 + x + 12 + x

b. Using multiplication and addition, write an expression to find the perimeter of the square.

Possible Solution: 4(12 + x) ; 4(12) + 4(x)

6. Juan says the two expressions 6(4a – 4) + 6a and 10a – 24 are equivalent. Is he correct? Explain why or why not. No. Using the distributive property the expression becomes 24a – 24 + 6a, then when you combine like terms you get 30a – 24.