Question

1. the crawford family used 7 kilowatt - hours of electricity in 3 days. at that rate, how many days would it take them to use 50 kilowatt - hours of electricity? (round your answer to one decimal place.)

Explanation:

Step1: Find daily electricity usage rate

The family uses 7 kWh in 3 days, so the daily rate $r$ is $\frac{7}{3}$ kWh per day.

Step2: Set up proportion for 50 kWh

Let $d$ be the days for 50 kWh. We have $\frac{7}{3}=\frac{50}{d}$ (since rate is constant). Cross - multiply: $7d = 3\times50$.

Step3: Solve for $d$

$7d=150$, so $d=\frac{150}{7}\approx21.4$ (rounded to one decimal place).

Answer:

21.4