The common factors of 64 and 100 are 1, 2, 4, and 8 .
These numbers are cubes of the numbers 1,2,3,5 & 6, respectively. So 43 is missing, which is 64. It should go between 27 and 125.
1, 5, 25, 125.
15 can of course go into 125, but not an even number of times. 125 / 15 = 8-1/3
Not evenly. 125 is an odd number and 2 can only go into even numbers evenly.
The number 1.
Only 1.
Every number below 42 will go into 125 three times.
1, 2, 4, 8, 16, 32, 64.
The HCF is 125
The HCF is 125
Only the number 1.