Question

15% of Alina’s workout consisted of cardio exercise. 25% of Dane’s workout consisted of cardio exercise. Which statement must be true?
If they worked out for the same amount of time, Dane did 10 more minutes of cardio exercise than Alina.


If Alina’s workout was 80 minutes, and Dane’s workout was 48 minutes, they spent the same amount of time on cardio exercise.


If both workouts were 60 minutes, Dane spent 8 more minutes on cardio exercise than Alina did.


Alina spent less time on cardio exercise than Dane did.

Answer 1

Answer:

If Alina’s workout was 80 minutes, and Dane’s workout was 48 minutes, they spent the same amount of time on cardio exercise.

Step-by-step explanation:

For option A,

If they both workout for $x$ minutes,

Alina's time is

$=0.15x$

and Dane's time is

$=0.25x$

The difference is

$0.25x-0.15x=0.1x$

If they both work out for 100 minutes, then Dane did 10 more minutes of cardio exercise than Alina.

Since $x$ is not fixed, this statement is false.

For option B,

If Alina's work out  was 80 minutes, then she spent $0.15\times80=12$ minutes on cardio exercise.

If Dane's work out  was 48 minutes, then he spent $0.25\times48=12$ minutes on cardio exercise.

Hence both spent the same amount of time on cardio exercise.

The correct answer is option B

For option C,

If they both workout for $60$ minutes, then

Alina's time is

$=0.15\times 60=9$

and Dane's time is

$=0.25\times60=15$

The difference is

$15-9=6$

If they both work out for 60 minutes, then Dane did 9 more minutes of cardio exercise than Alina and not 10.

This statement is false

For option D,

We cannot tell whether Alina spent more or less time than Dane,unless we know the time both spent for the entire work out.

Answer 2

Since the time difference depends on the initial amount of time, answer #1 is not right
Next, #3 is also not right since the difference is way to great.
Next, #4, we cannot tell how long the workouts of both were, so this is not right either
Therefore, #2 is the right answer
Hope this helped!! :D