81 is 54% of what number?

2 Answers
Jan 30, 2016

#81 = (54)/(100)*x to x = 100/54*81 = 150#

Explanation:

Percentages are fractions out of 100 of something. In this case, 54% is #54/(100ths)# of an unknown number, which we can call #x#. This is equal to 81.

#54/100*x=81#

Rearranging to make #x# the subject and solving:

#x=81*100/54 = 150#

Jan 31, 2016

#150#

Explanation:

#81=x(54/100)#

#rarr81/x=54/100#

Cross multiply:

#rarr81*100=54x#

#rarr8100=54x#

#rarrx=8100/54=4050/27=1350/9=450/3=150#