How do you find a percentage of a number without a calculator?

Divide the specific number by the total number and multiply the numerator by 100 since percentage is x/100

example :
there are 15 blue crayons in a box of 75 crayons.
what is the percentage of blue crayons?
15 = 1 * 100 = 100 = 20% 
75    5               5 

i hope this helps :)

24000-16186=7814

Step-by-step explanation:

7814÷4=1953•5