Find the whole. Explain your method

25% of 64

25% * 64 =

(25 : 100) * 64 =

(25 * 64) : 100 =

1,600 : 100 =

16;

Percentage solution with steps:

Step 1: Our output value is 64.

Step 2: We represent the unknown value with $x$x .

Step 3: From step 1 above,$64=100/%$64=100% .

Step 4: Similarly, $x=25/%$x=25% .

Step 5: This results in a pair of simple equations:

$64=100/% (1) $64=100% (1) .

$x=25/% (2) $x=25% (2) .

Step 6: By dividing equation 1 by equation 2 and noting that both the RHS (right hand side) of both

equations have the same unit (%); we have

$/frac{64}{x}=/frac{100/%}{25/%}$

64

x =

100%

25%

Step 7: Again, the reciprocal of both sides gives

$/frac{x}{64}=/frac{25}{100}$

x

64 =

25

100

$/Rightarrow x=16$⇒x=16