x = liters of 40% solution
y = liters of 70% solution
Gabe needs 30 liters, so
x + y = 30
Each liter of 40% solution contributes 0.4x liter of acid; each liter of 70% solution contributes 0.7y liter of acid. Gabe needs a solution with concentration 60%, which from 30 liters amounts to a net volume of 0.6*30 = 18 liters of acid. So
0.4x + 0.7y = 18
Solve the system however you like. By substitution, we have
y = 30 - x
0.4x + 0.7(30 - x) = 18
0.4x + 21 - 0.7x = 18
3 = 0.3x
==> x = 10 ==> y = 20
Sn = a1 * (1 - r^n)
----------
1 - r
n = 5 so answer =
1 * (1 - (1/2)^5
--------------- = 31/16
1 - 1/2
Answer:
36
Step-by-step explanation:
6 1/3 cups served is 18 so add another 18
What you must do for this case is find a function that suits the problem and graph it.
We have:
y: the number of bales in the barn
x: days feeding his cows.
y = -4x + 60 see graphic attached.
It depends how high it is