SOLUTION: You are making 10 tons of concrete that is 36.2% cement by mixing a 17% cement mix- ture with a 65% cement mixture. a) How much of the 65% cement mixture must you use? Answer

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Question 435249: You are making 10 tons of concrete that is
36.2% cement by mixing a 17% cement mix-
ture with a 65% cement mixture.
a) How much of the 65% cement mixture
must you use?
Answer in units of tons.
Found 2 solutions by ewatrrr, josmiceli:
Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website!

Hi
making 10 tons of concrete
Let x and (10-x) represent the amount of 65% and 17% cement mixtures respectively
Question states***Mixing to form 10 tons of 36.2% mixture
.65x + .17(10-x) = .362*10
.48x = .192*10
x = .192*10/.48
x = 4 tons of the 65% mixture needed
CHECKING our Answer***
.65*4 + .17*6 = 3.62

Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
Let = tons of 17% mixture needed
Let = tons of 65% mixture needed
given:
(1) tons
(2)
------------------------
(2)
(2)
Multiply both sides of (1) by
and subtract (1) from (2)
------------------------
(2)
(1)

and, since
(1)

6 tons of 17% mixture are needed
4 tons of 65% mixture are needed
check:
(2)
(2)

OK