Example 2.44 from Prealgebra, 2.4 Find Multiples and Factors

Find Multiples and Factors: example 2.44

Determine whether $1,290$ is divisible by $2, 3, 5, and 10 .$

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Solution

Table 2.11 applies the divisibility tests to $1,290 .$ In the far right column, we check the results of the divisibility tests by seeing if the quotient is a whole number.

Divisible by…?	Test	Divisible?	Check
$2$	Is last digit $0, 2, 4, 6, or 8 ?$ Yes.	yes	$1290 \div 2 = 645$
$3$	$Is sum of digits divisible by 3 ?$ $1 + 2 + 9 + 0 = 12$ Yes.	yes	$1290 \div 3 = 430$
$5$	Is last digit $5$ or $0 ?$ Yes.	yes	$1290 \div 5 = 258$
$10$	Is last digit $0 ?$ Yes.	yes	$1290 \div 10 = 129$

Table 2.11

Thus, $1,290$ is divisible by $2, 3, 5, and 10 .$

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Determine whether the given number is divisible by $2, 3, 5, and 10 .$

$6240$

How did it go?