Question

The fastest running time for 100m is 9.6 seconds. If you can run 100m in 10.8 seconds, what is the percentage decrease, rounded to the nearest one percent, needed for you to equal the world record?

A) 10%
B) 11%
C) 12%
D) 13%

Answer 1

To match the world record 100m time, a decrease of B) 11.11% (rounded to 11%) from the student’s current time of 10.8 seconds is needed, calculating the difference followed by division and conversion to percentage.

Step-by-step explanation:

The question is asking to calculate the percentage decrease in time required to equal the world record in a 100m sprint. We start with your current time of 10.8 seconds and want to reach the world record time of 9.6 seconds. Here are the steps for the calculation:

1. Find the difference in time: 10.8 s - 9.6 s = 1.2 s.
2. Divide the difference by your current time: 1.2 s / 10.8 s.
3. Convert the result into a percentage: (1.2 s / 10.8 s) × 100% = 11.11%, which rounded to the nearest one percent is 11%.

Therefore, the percentage decrease needed for you to equal the world record is 11% (Option B).