Step-by-step explanation:
n(s)=28
n(p)=14
p(p)= n(p)/n(s)
= 14/28
=1/7
Answer:
B) -x+8y=56
Step-by-step explanation:
y=1/8x+7
Multiply by 8 to clear the fraction
8y = 8(1/8x+7)
Distribute
8y = 8*1/8x +8*7
8y = x+56
Subtract x from each side
-x+8y = x-x+56
-x+8y = 56
Let t, f, and s be the amount of 25%, 40%, and 60% solutions used.
We are told s=3f. The general equation is:
100(0.25t+0.4f+0.6s)/(t+s+f)=45, and using s=3f we have:
(0.25t+0.4f+1.8f)/(t+4f)=0.45
(0.25t+2.2f)/(t+4f)=0.45
0.25t+2.2f=0.45t+1.8f
0.25t+0.4f=0.45t
0.4f=0.2t
t=2f, remembering that s=3f, will allow us to solve for f
t+s+f=60, using t and s from above
2f+3f+f=60
6f=60
f=10 L then
s=3f=30 L and t=2f=20L
So 20L of 25%, 10L of 40%, and 30L of 60% acid solutions need to be mixed to make 60L of 45% acid solution.
The answer is C: 6x^3 - 24x^2 + 9x + 30
