Answer:
The number of gallons of 20% alcohol solution is 12 and the number of gallons of 60% alcohol solution is 4
Step-by-step explanation:
Let
x ----> the number of gallons of 20% alcohol solution
y ----> the number of gallons of 60% alcohol solution
we know that
20%=20/100=0.20
60%=60/100=0.60
30%=30/100=0.30
x+y=16
x=16-y ------> equation A
0.20x+0.60y=16(0.30) ------> equation B
Solve by substitution
Substitute equation A in equation B and solve for y
0.20(16-y)+0.60y=16(0.30)
3.2-0.20y+0.60y=4.8
0.40y=4.8-3.2
0.40y=1.6
y=4 gal
Find the value of x
x=16-y
x=16-4=12 gal
therefore
The number of gallons of 20% alcohol solution is 12 and the number of gallons of 60% alcohol solution is 4