Question

If it took 2.5 gallons of paint to cover 282 square feet of wall, how much paint is needed to paint an additional 423 square feet

Answer 1

its 3.75 gallons because half of 282 is 141 and 141+282=423. So add half of 2.5 to the amount of gallons you have and you should get 3.75. Half of 2.5 is 1.25 and 1.25+2.50=1.75      (2.50 is the same thing as 2.5)