Question

Sumaya can manufacture a spark plug in 13 minutes. When her friend Leonardo helps her, it takes them 5.32 minutes. Using a rational equation, which of the following correctly calculates the rate Leonardo manufactures spark plugs, rounded to the nearest hundredth?(1 point)

69.16 minutes

2.44 minutes

5.32 minutes

9.01 minutes

Answer 1

Let L be Leonardo's minutes per plug. Rates add:
1/13 + 1/L = 1/5.32
1/L = 1/5.32 − 1/13 = 7.68/69.16
L = 69.16/7.68 ≈ 9.01 minutes

Answer: 9.01 minutes.