SOLUTION: A water tank is 7/8 full. When 21 liters of water are drawn out, the tank is 5/8 full. What is the total capacity of the tank in liter? a)63 b)84 c)87 d)93

Algebra ->  Numeric Fractions Calculators, Lesson and Practice -> SOLUTION: A water tank is 7/8 full. When 21 liters of water are drawn out, the tank is 5/8 full. What is the total capacity of the tank in liter? a)63 b)84 c)87 d)93      Log On


   



Question 716598: A water tank is 7/8 full. When 21 liters of water are drawn out, the tank is 5/8 full. What is the total capacity of the tank in liter?
a)63
b)84
c)87
d)93

Answer by jndarrell(58) About Me  (Show Source):
You can put this solution on YOUR website!
If pulling 21L out only drops the tank 2/8...set your proportion from there. Part over whole = part over whole. Make sure your units match on both sides num/den.
21/x = 2/8
Cross multiply
2x = 168
Divide both sides by 2 to get x alone
x=84L
B
:)