Question

a 130 - pound person uses 5.1 calories per minute when walking at a speed of 4 mph. how long must a person walk at this speed to use at least 210 calories? a person must walk for at least minutes in order to use at least 210 calories. (round up to the nearest minute)

Explanation:

Step1: Set up the equation

Let $t$ be the time in minutes. The rate of calorie - burn is 5.1 calories per minute. We want to use at least 210 calories. So the inequality is $5.1t\geq210$.

Step2: Solve for $t$

Divide both sides of the inequality by 5.1: $t\geq\frac{210}{5.1}\approx41.176$.

Step3: Round up

Since we need to round up to the nearest minute, $t = 42$.

Answer:

42