Two times the sum of x and seven plus ten

Fanny mendelssohn manages all the magazines and paperback books at a local grocery store. she prices many paperbacks to sell at $7.99. the cost to the store is $5.29. what is the markup rate on a paperback book, based on its cost?

When solving this problem: 3025/5.5 = a/90.75 you get 49912.5 which would be the length of one of the sides of a square when the area is only 90.75 inches. is that answer correct, why, and how is it possible?

A. the probability that a product is defective is 0.1. what is the probability that there will be 1 or less defective products out of the next 8 produced products b.the expected number of imperfections in the coating nylon for parachutes is 6 per 100 yards. what is the probability of finding 12 or fewer imperfections in 260 yards c.in a lot of 54 products there are 9 defective products. calculate the probability that not more than 1 is defective from a random sample of 17 products.