42% of 42 is 84% of what number?

21

Step-by-step explanation:

42% of 42 is 84% of what number

Let the number be y

42% of 42 is 84% of y

NOTE: Of means multiplication

42/100 * 42 = 84 / 100 * y

1764/100 = 84y/100

cross multiply over the equal sign

176400 = 8400y

divide by 8400

176400/8400 = 8400y/8400

y = 21

To verify

42% of 42 is 84% of a number

42% of 42 is 84% of y

42/100 * 42 = 84/100 * 21

1764/100 = 1764/100

17.64 = 17.64