Final answer:
The number 21 is 12% of 175. You solve this by setting up a proportion (21/12% = x/100%) and then cross multiplying and dividing to find the value of x.
Step-by-step explanation:
To find out what number 21 is 12% of, you would set up a proportion in which 21 corresponds to 12%, and x corresponds to 100%, since percentages are out of 100. Therefore, the proportion is 21/12% = x/100%.
Next, you would cross multiply in order to solve for x:
21 ×100% = x × 12%
2100 = 12x
Now, to find the value of x, you would divide both sides of the equation by 12:
2100 / 12 = x
x = 175
So, 21 is 12% of 175.