A car radiator contains 8 liters of a 32% antifreeze solution. How many liters of this solution should be drained and replaced with pure antifreeze to get a 49% solution?

Question

anonymous · Answer

OKay so for this...
damn it i have to go okay sorry bye!!

anonymous · Answer

8 liters

anonymous · Answer

is 4L 2L 3L or 1.75

anonymous · Answer

drain 8 liters of 32% and replace 8 liters of 49%

dumbcow · Answer

haha thats the lazy way :)

anonymous · Answer

my only choices are 2 3 4 or 1.75 not 8

dumbcow · Answer

system of 2 equations
Let x be 32% antifreeze, y is amount drained and replaced
x+y = 8
.32x + y = .49

dumbcow · Answer

oops it should be 8*.49

use elimination
subtract row 1 - row 2
x      + y    = 8
-.32x -y = -(8*.49)
__________________
.64x  +0  = 4.08

x = 4.08/.64
x = 6.375

y = 8-x
y = 8-6.375
y=1.625

1.625L should be drained and replaced

dumbcow · Answer

wierd i did something really wrong
sorry
answer is 2L