How much paint is needed to paint the walls of a room 16x12x10? each gallon covers 400 square feet and each quart covers 100 square feet

That's true because 4 quart=1 gallon
1 quart=2 pint
1 pint=2cups
1 gal=400
1 qt=100
1 pint=50
1 cup=25
so find the area by multiplying
so assuming that 16=width
12=height
10=legnth
multiply (2 times 16 times 12)+(2 times 12 times 10)=(384)+(240)=624 square feet to cover so
you need 6 quarts and 1 cup or 1 gallon and 2 quarts and 1 cup or 21 cups

you need 6 quarts and 1 cup
if you are only allowed to use gallons and quarts the answer is 7 quarts or 1 gallon and 3 quarts or 1 3/4 gallon