4x + 9x = 13x i think

News cameras take an overhead picture of a crowd at an outdoor event journalist then count the total number of people in the picture and use the sample of estimate the total number of people in the crowd this process is an example of

Susie wants to take her friend out for lunch. she wants to spend $9.75 each person. how much will she spend in all.

I’m really confused and need to learn this