40 %
To find this answer, you first need to find the amount you will save (150 - 90 = 60) Then it is simply guess and check. I started by multiplying 150 by .5 (fifty percent) and got 75 dollars which is more than 60. So then I tried 150 times .4 (fourty percent) and I got sixty. Your answer is fourty percent. I hope this helps!
