Find the net pay for the week if John earns $423.60, is taxed $67.80, pays $32.10 for voluntary fund and has miscellaneous deductions totaling $76.30.
What percentage of his gross pay did he pay in tax?

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

answer: the answer is 100 x 12,500, which is 1,250,000.

step-by-step explanation: emily solved for a part when she should have solved for the whole.  

875,000 should be the numerator of the equivalent ratio.  

70 x 12,500 is 875,000.