Sylvie is mixing concrete for her patio. For every 26.7 pounds of concrete mix, she needs to add 1 quart of water. Sylvie buys 80 kilograms of concrete mix
1 kilogram 2.2 pounds
How many quarts of water, rounded to the nearest tenth, does Sylvie need to add to 80 kilograms of concrete mix?
quarts

b

step-by-step explanation:

a difference is the result of subtraction. while each of these expressions has subtraction in it, a difference will be the result when subtraction is the last operation applied in the order of operations for the expression. this means subtraction must be outside of the parenthesis. only b has this.

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4