radiator ha 13 quarts of fluid, 30% is antifreeze. How much fluid should be drained and replaced with antifreeze so the new mixture is 55% antifreeze?

Question

Round to hundreths

Answer 1

13 quarts of 30% antifreeze

drain X quarts and replace with 100% antifreeze

to get 13 quarts of 55% antifreeze

13(.3) - .3X + X = 13(.55)

.7X = 13(.55-.3) = 13(.25) = 13/4 = 3.25

X = (10/7)(13/4) = 130/28 = 4.643 quarts should be drained and replaced with 4.643 quarts of 100% antifreeze