Step-by-step explanation:
let,the sum of the ages of chukwu & Caroline be X & Y.
now,
X+y=45
X-y=3
(+) (+) (-)
__________
2x=42
or,X=42/2
or,X=21
putting the value of X,
X+y=45
or, 21+y=45
or,y=45-21
or,y=24
therefore,X=21
y=24
Answer:
8.46 gallons needed to be replaced
Step-by-step explanation:
Let x be the alcohol amount that replaced
-Original has concentration of 15% multiply by the amount of 10 ,which is equal to (0.15×10).
-Removed has concentration of 15% multiply by the amount of x ,which is equal to (0.15 × X).
-Added has concentration of 80% multiply by the amount of X ,which is equal to (0.8× X).
-Solution has concentration of 70% multiply by the amount of 10 ,which is equal to (0.70×10).
So that, the equation will be:
Solution=Original + added - removed
7=1.5+0.8x-0.15x
7-1.5=0.65x
0.65x=55
x=55/0.65
x=8.46
8.46 gallons needed to be replaced.
Answer:
84%
Step-by-step explanation:
of the means division.
42/50 = 84/100 = 84%
