Answer:
The battery was 19 percent full
It will take 32.4 minutes for the battery to be fully charged
Step-by-step explanation:
Each minute, the percentage of the battery's capacity that was charged increased by 2.5
There is a constant increase for every minute, so m= 2.5
We use equation y = mx+b
After 17 minutes of charging, the battery was 61.5 percent full.
When x= 17 , y= 61.5. we know m = 2.5. solve for b
y=mx+b
61.5 = 2.5(17) + b
61.5 = 42.5 + b
Subtract 42.5 on both sides
b= 19
The battery was 19 percent full
To get full charge then y =100 percent
We plug in 100 for y and solve for x
y=mx+b , m= 2.5 , b=19
100=2.5x + 19
Subtract 19 on both sides
81= 2.5x
divide by 2.5 on both sides
x= 32.4
It will take 32.4 minutes for the battery to be fully charged
