SBAC Math Grade 7 Ratios and Proportions 2

Question 1

A store sells 3 apples for $1.50. At this rate, how much do 7 apples cost?

Accepted Answer

$3.50

Answer

Unit rate: $1.50 ÷ 3 = $0.50 per apple. 7 × $0.50 = $3.50.

Question 2

A scale drawing uses 1 inch = 12 feet. If a room is 3.5 inches on the drawing, what is its actual length?

Accepted Answer

42 feet

Answer

Multiply the drawing measurement by the scale factor: 3.5 inches × 12 feet/inch = 42 feet.

Question 3

A car travels 150 miles in 2.5 hours. What is its average speed in miles per hour?

Accepted Answer

60 mph

Answer

Speed = distance ÷ time = 150 miles ÷ 2.5 hours = 60 miles per hour.

Question 4

What is 35% of 80?

Accepted Answer

28

Answer

35% of 80 = 0.35 × 80 = 28. Or: 35/100 × 80 = 2800/100 = 28.

Question 5

Is the relationship between x and y proportional? x: 2, 4, 6, 8 and y: 5, 10, 15, 20.

Accepted Answer

Yes, because the ratio y/x is constant at 5/2

Answer

The ratios y/x are 5/2, 10/4, 15/6, 20/8 — all equal to 5/2 = 2.5. Constant ratio = proportional relationship.

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