Step 1: We make the assumption that 68 is 100% since it is our output value.
Step 2: We next represent the value we seek with $x$x.
Step 3: From step 1, it follows that $100\%=68$100%=68.
Step 4: In the same vein, $x\%=40.8$x%=40.8.
Step 5: This gives us a pair of simple equations:
$100\%=68(1)$100%=68(1).
$x\%=40.8(2)$x%=40.8(2).
Step 6: By simply dividing equation 1 by equation 2 and taking note of the fact that both the LHS
(left hand side) of both equations have the same unit (%); we have
$\frac{100\%}{x\%}=\frac{68}{40.8}$
100%
x%=
68
40.8
Step 7: Taking the inverse (or reciprocal) of both sides yields
$\frac{x\%}{100\%}=\frac{40.8}{68}$
x%
100%=
40.8
68
$\Rightarrow x=60\%$⇒x=60%
Therefore, $40.8$40.8 is $60\%$60% of $68$68.