(3a) 3 = this expression without exponents is 3aaa 3·3·3a 3a3a3a 3·3·3a 3

Julie goes to the sports store and spends $40.50 before tax. she buys a pair of shorts for $21.75 and 3 pairs of socks that each cost the same amount. how much does each pair of socks cost? $$