30% of a number is 120. What is the number?

2 Answers
Jul 2, 2017

Answer:

#400#

Explanation:

You divide #120/0.3=400#

You can double check by multiplying #400xx0.3=120#

Jul 2, 2017

Answer:

#n=400#

Explanation:

If we choose #n# as the number, we can write an equation:

#30% " of " n = 120" "larr# now solve for #n#

#30/100 xx n =120#

#n = 120 xx 100/30#

#n = 400#

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Or we can write equivalent fractions for the numbers and percentages as a direct proportion:

if #120# is #30%#, then what number will be #100%?#

#120/30 = x/100" "(larr"numbers")/(larr"percents")#

#30x = 120xx100" "larr# cross multiply to get this

#x = (120xx100)/30#

#x =400#