Abattery was charged. when the changing began, it was 23 percent full. after 30 minutes of charging, the battery was 89 percent full? how long did it take to fully charge in minutes?

Attached the solution and work.

6xy and -16xy000000000

38+105= 143, 39+104=143, and you will find then adding the numbers on opposite sides, moving inwards yields the answer 138 every time. because of this, you’re going to multiply 138 times the number of pairs, which is 34. therefore, 34*138= 4692(i’m sorry if it’s the wrong numbers, but it’s the right concept)