Jeremy bought postcards on a trip. He sent 5 cards to his aunt. He sent half of the remaining cards to his friends. Then he sent one of the remaining cards to his sister. He was left with 4 cards. Find out how many postcards Jeremy bought.
'x' = number of postcards
sends off 5 now has x-5 remaining
sends off 1/2 now has 1/2 (x-5) remaining
thens sends one to sis 1/2 (x-5) -1 remaining and this equal 4
1/2 (x-5) -1 = 4 solve for 'x' the number of postcards he purchased....