Question

The music for Nadia’s dance routine last for exactly 4 minutes. When Nadia dances her routine, she starts with her music and finishes 12 seconds before the music ends. What percent of the time the music is playing is Nadia dancing?

Answer 1

4 x 60 = 240 seconds


`(12)/(60) / (12)/(12) = (1)/(5)` of a minute not dancing.


`4 * 5 = 20 - 1 = 19`
`(19)/(20) * (5)/(5) = (95)/(100)`

95% of the time dancing

Answer 2

Nadia's routine is around 0.95 times the duration of the music.

Explanation:

Givens:

• The routine last 4 minutes.
• She finished 12 seconds before the music ends.

Basically, the music is 12 seconds more than the routine, that is, the music last 4 minutes and 12 seconds, which have to transform to just minutes to find the ration between both durations.

`12sec(1min)/(60sec)=(3)/(15)min=(1)/(5)min`

So, the music is
`4(1)/(5) min`. Now to find the percentage of the music is Nadia's routine, we just have to divide:

`4(1)/(5) / 4=(5)/(21) * 4=(20)/(21) \approx 0.95`

Therefore, Nadia's routine is around 0.95 times the duration of the music.