1, since 17 is a Prime number.
90 does 90 goes in twice 90 * 90 = 8100
The highest number that goes into both 90 and 147 is 3.
The number 1 goes into both 17 and 42. In this instance, one goes into each number exact the same number of times as the original number like 17 or 42.
Oh, dude, let me do some quick math in my head... 17 goes into 90 around 5 times with a remainder of 5. So, like, you can fit 5 seventeens in there, but there's a little bit left over. Math can be so demanding, right?
15.3
1 and 17. It is a prime number
1 is the only number as 17 is a prime number
3. 6. 9. 10. 15. 30. 90.
Only 1 and 17, since 17 is prime. ■
There is no number except 1 which can divide both 17 and 90. So, GCF = 1.
90
That number is 1.