Question 1127082
<br>
Here is a simple alternative to the standard algebraic method for solving mixture problems.  If you understand how to use it, you will get to the answer much faster and with far less work.<br>
Here is the whole solution process by this alternative method.<br>
(1) 90% is 5/6 of the way from 40% to 100%.  (Do some simple mental calculations: 90-40 = 50; 100-40 = 60; 50/60 = 5/6)<br>
(2) Therefore, 5/6 of the mixture must be the higher percent juice.<br>
(3) 5/6 of 4 liters is 20/6 = 10/3 liters.<br>
ANSWER: 10/3 liters of pure apple juice