Question 1130543
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20 liters of paint consist of 2+3 = 5 equal parts; so each part is 4 liters; hence, white paint is 8 liters  (and blue paint is 12 liters).


To get the final ratio white to blue as 1:7, Mary must have 7*8 = 56 liters of the blue paint - so she need to add 56-12 = 44 liters.


<U>Answer</U>.  44 liters of the blue paint to add.
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