# John is using his phone while it is charging. The phone gains 10% every 3 minutes and it drains 7% every 5 minutes. How long will it take his phone to gain a 20% charge?

##### 1 Answer

Feb 8, 2018

#### Answer:

The time required for 20 percent charge gain is

#### Explanation:

percentage gain of charge:

10 in 3 minutes

percentage gain of charge per minute

If it is charged for

percentage gain of charge in

percentage drain of charge:

7 in 5 minutes

percentage gain of charge per minute

In the same time,

percentage drain of charge in

net gain = gain - drain

For net gain to be 20 percent

Solving for x

The time required for 20 percent charge gain is