So, he's got 8 gallons of paint, to paint the two rooms, of the two rooms, one is twice as big as the other
now, "x" is how many gallons to paint the larger room with only one coat, however, the larger room uses 2 coats, so, the larger room uses 2x of paint
now, the client declined to paint the smaller one
so hmmm as I read... well, we dunno how many coats will go to the smaller room for one, we know the larger will use 2 coats, or 2x.. if we assume the smaller room was going to use say 1 coat or 1/2x
then one can say the painter bought enough for both rooms, 1coat for the small one and 2coats for the larger one
so, the paint the larger room, you'll 2x of paint, for 2coatsand to paint the smaller room, you'll need 1/2 x, because x gallons is how much is needed for the larger room, but the larger room is twice as big, thus the smaller room uses 1/2 of that in gallons
thus, with those assumptions, that the small room will use only 1 coat
that's who many gallons are needed for 1 coat in the larger roomrecall "x" is 1coat for the larger room
now, the client decides to skip the smaller roomso, the painter will only need 2x gallons then
he bought 8 gallons, 8 - 6.4, he's got left 1.6 gallons
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