Question

a hard drive is 80% full and has 12000 megabytes of free space. one minute of video uses 60 megabytes of storage. How many minutes of video should be deleted so that the hard drive is 75% full?

Answer 1

Solution: Let x be the total space of hard drive.

We are given 80% space of hard drive is full and 12000 megabytes are free.

We can write:

$x-80\% \times x=12000$

$x-\frac{80}{100}x =12000$

$\frac{100x-80x}{100}=12000$

$20x=12000 \times 100$

$x=\frac{1200000 }{20}$

$x=60000$ megabytes

We have to free 5% of space as the difference between 80% and 75% is 5%.

Therefore 5% of 60000 is:

$\frac{5}{100} \times60000=3000$

We know that 1 minute of video uses 60 megabytes of space.

Therefore number of minutes of video that should be deleted to make 75% of space free is:

$\frac{3000}{60}=50$ minutes of video

Hence, 50 minutes of video should be deleted so that the hard drive is 75% full.