Answered

Which of the numbers 1, 6, 9, 7, 8 is a factor of 21?

Sagot :

Jers15viz
The factors is 21 is 1, 3, 7, 21.

Therefore in the choices above, the factors of 21 is 1 and 7.

Hope this helps =)
JVsCoviz
In getting the factors, you must get the divisibility number of the given number.
Example:
   21 is divisible by: 1 (multiplied by itself, and 21 is divisible by 7) and 7 (multiplied by 3 to get 21 which is divisible by 7).