Let’s remember the most basic thing in percentages, the equation.
Percent x Whole = Part.
We know the whole, and the part, but we are trying to find the percent, so we have to divide the two, first turn your whole and part into a decimal.
Percent x 0.4 = 0.18, so we divide 0.18 by 0.4
0.18/0.4 = 0.45
0.45 = 45%
You want to get x on one side so you divide both sides by 7 and 35/7 = 5
Volume of water in the glass = 3 x 2 x 4 = 24 cubic cm.
Volume of water plus the ring = 3 x 2 x 4.25 = 25.5 cubic cm.
Subtract the total with the ring from just the water:
25.5 - 24 = 1.5 cubic cm
