X represents the full tank so 2/9x+12=2/3x solve for x 2/9x+12=2/3x try to convert 2/3 to a commom denomenator (bottom numer ) 2/3=6/9 2/9x+12=6/9x subtract 2/9x from both sides 12=4/9x mulitply both sides by 9 to get rid of fraciton 108=4x divide by 4 27=x
