Jordan K. answered 09/05/15
Tutor
4.9
(79)
Nationally Certified Math Teacher (grades 6 through 12)
Hi Araceli,
Let's begin by assigning a letter to represent our unknown:
x = number of gallons of 100% concentrate
Now let's write an equation using the numerical information given in the problem and our unknown (x) to express the mixing of the two concentrates giving our final mixture's concentration:
100% Concentrate = (1.00)(x)
42% Concentrate = (0.42)(53)
71% Concentrate = (0.71)(x + 53)
(1.00)(x) + (0.42)(53) = (0.71)(x + 53)
Now let's solve this equation for our unknown (x):
(1.00)(x) + (0.42)(53) = (0.71)(x + 53)
x + 22.26 = 0.71x + (0.71)(53)
x + 22.26 = 0.71x + 37.63
x - 0.71x = 37.63 - 22.26
0.29x = 15.37
x = 15.37 / 0.29
x = 53 (number of gallons of
100% concentrate)
We can verify our answer by plugging it back into our equation and checking to see that both sides are equal:
(1.00)(x) + (0.42)(53) = (0.71)(x + 53)
(1.00)(53) + (0.42)(53) = (0.71)(53 + 53)
53.00 + 22.26 = (0.71)(106)
75.26 = 75.26 (both sides are equal)
Since both sides are equal, we are confident that our answer is correct.
Thanks for submitting this problem and glad to help.
God bless, Jordan.