Question

What is a number between 80 and 100 with at least 3 factors and one of them is 5? HELP

Answer 1

someone help me

Answer 2

first list all the numbers between 80 and 100 that can be divided by 5

Answer 3

85 90 95

Answer 4

divide each by 5 (to simplify them)
what do you get ?

Answer 5

^^
do that to get the other factors of 85,90, and 95

Answer 6

85/5=17
90/5=18
95/5=19

Answer 7

yes, that is my idea

Answer 8

now look for a number that has at least 2 factors
notice two of them are prime (no more factors, except themselves and 1 )

Answer 9

im confused

Answer 10

do you agree 17 is prime ?

Answer 11

yes

Answer 12

Here is a list of prime numbers
http://metricconversion.biz/list-of-first-100-prime-numbers.html

primes do not factor

Answer 13

and so is 19

Answer 14

notice 85= 5*17
both 5 and 17 are prime numbers. that means they cannot be factored.
in other words, 85 has exactly two factors , namely 5 and 17
but you want a number with at least 3 factors.
so cross 85 off your list as a possible answer.

Answer 15

yes, which leaves
90= 5*18

but 18 is not prime, so it can be factored