Question

. Archie's gas tank is 1/3 full. If Archie adds 3 gallons of gas to the tank, it will be 1/2 full. What is the capacity in gallons of Archie's tank?

Answer 1

lets say x gallons is the capacity of tank....
initially, tank has x/3 gallons
after Archie adds 3 more gallons, x/3+3=x/2
solve for x

Answer 2

\[\frac{ 1 }{ 3 }x+3=\frac{ 1 }{ 2 }x\]

Multiply each term by 6
2x + 6(3) = 3x
18 = 3x - 2x
x = 18