To find out how many quarts there are in 40 gallons, we simply need to know how many quarts there are in one gallon. As the name implies, there are 4 quarts in one gallon, so we simply need to multiply 4 * 40 to find the amount of quarts in 40 gallons.
4 * 40 = 160
There are 160 quarts in 40 gallons. Hope that helped! =)
There are 4 quarts into a gallon, so if you have 2 gallons, you would times the 2 gallons by 4 guards. For this, you take 4 quarts times 40 gallons. You get the answer 160!