You can set up an inequality with each of these. is/of = %/100
In this case you'd be solving for each of the "is".
(1) X/8.72=5/100
100X = 43.6
X= .436
(2) X/0.0436=5/100
100X=0.218
X= 0.00218
(3) X/0.436=5/100
100X=2.18
X=0.0218
(4) X/4.36=5/100
100X=21.8
X=0.218
I've heard of the method referred to as the Heart Method. Try looking up YouTube videos on how to solve these types of problems.
