This is from the 2007-2008 test released by collegeboard from section 2 question 17.
THe graph above shows the amount of water remaining in a tank each time a pail was used to remove x gallons of water. If 5 gallons were in tank orginially and 5/3 gallons remained after the last pail containing x gallons was removed, what is the value of x?
Umm…I think you mistyped this (or just miscalculated the mixed fraction). The original question says gallons are left. That’s not 5/3, that’s 7/3!
Anyway, the graph tells you that 8 pails were removed. And you know that 5 – 7/3 = 8/3 gallons were removed in total. 8 pails totaling 8/3 gallons means each pail was 1/3 of a gallon.