So lets go step by step, first lets see how much Reagan spent, that is 2 banana splits, $3.25 each, that is:
total spent = 2*3.25 = 6.50
So Reagan spent $6.50 of her weekly allowance, and the problem says that $6.50 represents 26% of her weekly allowance, the question is to find out how much represents the 100% of her weekly allowance.
We can solve this using a rule of three, simple, with direct proportion:
26% -----> $6.50
100% ----> x
x = (100)(6.50)/26 = 650/26
x = 25
therefore Reagan's weekly allowance is $25
