4x10^8 has how many times more than 5 x 10^7

Ifurniture stores having a weekend sale and is offering 20% discount on patio chairs and table the sales tax on furniture is 6.25 using function composition how can you represent the total amount a that you would need to pay for this furniture that cost x dollars

Pat listed all the numbers that have 15 as a multiple write the numbers in pats list

If x is 6, then 7x= a. 13 b. 42 c. 42x d. 76