Mark charged a battery. Each minute, the percentage of the battery's capacity that was charged increased by 2.5 percent. After 17 minutes of charging, the battery was 61.5 …

Question

asked Jan 9, 2018 215k views

2 Answers

Fishsticks · Answer 1 · 2018-01-11T00:12:52+0000

I'm not sure if this is correct but I made this into the equation 61.5=17+2.5x. I solved the equation and the answer I got is 17.8%

Hatted Rooster · Answer 2 · 2018-01-15T18:27:40+0000

Answer: The battery was 19 percent full when the charging began.

Explanation:

Since we have given that

Every minute, the percentage of the battery's capacity increased by = 2.5%

As we know that "Equation of line ":

$y=mt+b\\\\Here, \\\\\text{ 't' represents number of minutes and 'b' represents initial battery }$

So, our equation becomes for now,

y=2.5t+b

As we have given that,

After 17 minutes, the battery was 61.5% full.

So, our coordinate becomes (17,61.5)

So, it becomes

$61.5=2.5* 17+b\\\\61.5=42.5+b\\\\61.5-42.5=b\\\\19=b$

Hence, the battery was 19 percent full when the charging began.