3x - 15 = 7 - 8x how do you solve this

Five dinosaurs go for a walk and come across some lovely chicken wings. their names are rexy, bronto, steggy, paly, and terry. there are exactly 5 dozen wings(equal enough for each dino to have a dozen right? ); however, terry is on a diet and he only eats 6 wings. if paly eats 2 more than terry, steggy eats 4 more than paly, and bronto and rexy eat the same amount because they are really hungry from not eating all day, how many chicken wings did each dino eat?

If 24 people have the flu out of 360 people, how many would have the flu out of 900. choose many ways you could use proportion that david would use to solve this problem

The jewelry store is having a sale. necklaces that were regularly priced at $23.50 are on sale for $18.80. what is the percentage of decrease in the price of necklaces?