Answer:
15 hours
Step-by-step explanation:
is the number of hours that Liam volunteered in the first month
The next month he volunteered 
times the time he volunteered the first month.
Total time he volunteered in the two months is 40 hours so
Time he volunteered in the first month is 15 hours.
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.
0+a+b
a=2
b=10
0+2+10=12/3=4
4=2a
5a is the answer.
Answer:
P = -7
Step-by-step explanation:
-10p - 4 = 66 you take and isolate the -10p by adding 4 to both sides since 4 is negative in the problem then you get -10p = 70 and to get rid of the -10 you divide 70 by -10 to get P = -7.
