Business Mathematics Brief 12th Edition by Stanley Salzman ,Gary Clendenen, Charles Miller

Exercise 37

Put a check mark in the blank if the number at the left is evenly divisible by the number at the top. Put an X in the blank if the number is not divisible. (See Example.)
Using the Divisibility Rules
Determine whether the following statements are true.
(a) 3,746,892 is evenly divisible by 4.
(b) 15,974,802 is evenly divisible by 9.
Quick TIP
Testing for divisibility by adding the digits works only for 3 and 9.
SOLUTION
(a) The number 3,746,892 is evenly divisible by 4, since the last two digits form a number divisible by 4 without remainder.

(b) See if 15,974,802 is evenly divisible by 9 by adding the digits of the number.

Since 36 is divisible by 9, the given number is divisible by 9. The rules for divisibility help determine only whether a number is evenly divisible by another number. They cannot be used to find the result. The division must actually be done to find the quotient.