Question

max is training for a triathlon. he recorded the time for each portion of the race during his practices. max wants to know which event had the most improved time. what is the percent decrease in maxs swim time? triathlon event | maxs first practice time (min) | maxs last practice time (min) | amount of change (min) | percent decrease
running (10 k) | 80 | 68 | 12 | 15
swimming (1.5 k) | 60 | 48 | 12 |
biking (40 k) | 90 | 81 | 9 |
(all even has occurred please enter a number)

Explanation:

Step1: Recall percent decrease formula

Percent Decrease = $\frac{\text{Amount of Change}}{\text{Original Time}} \times 100\%$

Step2: Identify swim time values

Original swim time = 60 min, Amount of change = 12 min

Step3: Calculate percent decrease

$\frac{12}{60} \times 100\% = 0.2 \times 100\% = 20\%$

Answer:

20%