Answer:
C. 81
SOLUTION:
Step 1: Our output value is 90.
Step 2: We represent the unknown value with [tex]x.[/tex]
Step 3: From step 1 above, 90 = 100%
Step 4: Similarly, x = 90%
Step 5: This results in a pair of simple equations:
90 = 100%(1)
x = 90%(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
[tex]\frac{90}{x} = \frac{100^{0/_{0} }}{90^{0/_{0} } }[/tex]
Step 7: Again, the reciprocal of both sides gives
[tex]\frac{x}{90}= \frac{90}{100} \\\\x= 81[/tex]
Therefore, 90% of 90 is 81
Step-by-step explanation:
