30% off 25: multiply 25 by .30 to find 30%: 7.5. Now subtract that from the sales price: 25-7.5=17.5 Do the same for store B: .40•30=12. 30-12=18. So store A is better by $.50 :) hope this helps :)
Store A is $25.00-30% is 7.50 savings= buying it for 17.50 Store B is $30.00-40% is 12.00 savings = buying it for 18.00 Making store A a better deal by $0.50