When finding a percent, what do you do? for example "what is 24% out of 45"

We have an equation: ?/45= 24/100

Cross multiply:
100*? = 24*45
⇒ ?= 24*45/100= 10.8

24% out of 45 is 10.8~

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)