Question

Question 9 (5 points)

(03.04 LC)
The sum of two numbers is 52. The greater number is 4 more than the smaller number. Which equation can be used to solve for the smaller number? (5 points)

a
x − (x + 4) = 52

b
x + (x + 4) = 52

c
x(x + 4) = 52

d
x(x − 4) = 52

Question 10 (5 points)
(03.05 MC)
Gavin needs $80 to buy a fish tank. He has saved $8 and plans to work as a babysitter to earn $9 per hour. Which inequality shows the minimum number of hours, n, that Gavin should work as a babysitter to earn enough to buy the fish tank? (5 points)

a
8 + 9n ≥ 80, so n ≥ 8

b
8 + 9n ≤ 80, so n ≤ 8

c
9n ≥ 80 + 8, so n ≥ 9.8

d
9n ≤ 80 + 8, so n ≤ 9.8

Question 11 (5 points)
(03.05 MC)
Natalie works in a toy shop and earns $43 per day. She earns an extra $3 for each toy she sells. If Natalie wants to earn at least $70 per day, which inequality shows the minimum number of toys, n, that she should sell? (5 points)

a
43 + 3n ≥ 70, so n ≥ 9

b
43 + 3n ≤ 70, so n ≤ 9

c
43 + 3n ≥ 70, so n ≥ 24

d
43 + 3n ≤ 70, so n ≤ 24

Question 12 (5 points)
(03.05 MC)
Chad wants to buy some books over the Internet. Each book costs $10.01 and has a shipping cost of $9.96 per order. If Chad wants to spend no more than $50 for his books, which inequality shows the maximum number of books, p, that he can buy? (5 points)

a
9.96p − 10.01p ≤ 50, so p ≤ 1

b
9.96p + 10.01p ≤ 50, so p ≤ 2

c
9.96 − 10.01p ≤ 50, so p ≤ 3

d
9.96 + 10.01p ≤ 50, so p ≤ 4

Answer 1

• 9. B, 10. A, 11. A, 12. D

Explanation:

Question 9

The smaller number is x, the greater number is x + 4, their sum is 52:

• x + (x + 4) = 52

Correct choice is B

Question 10

$8 and 9n should sum at least $80:

• 8 + 9n ≥ 80 ⇒ 9n ≥ 72 ⇒ n ≥ 8

Correct choice is A

Question 11

$43 and 3n should sum at least $70:

• 43 + 3n ≥ 70 ⇒ 3n ≥ 27 ⇒ n ≥ 9

Correct choice is A

Question 12

P books cost $10.01p and $9.96 for shipping, the total should be no more than $50:

• 9.96 + 10.01p ≤ 50 ⇒ 10.01p ≤ 40.04 ⇒ p ≤ 4

Correct choice is D