If you mean whole numbers, then they are:
1, 2, 3, 5, 9, 10
A factor can divide into its multiple evenly.
7 is not a factor of 90. It does not divide into 90 evenly.
2 and 60 will divide evenly into 120.
1,2,3,5,6,9,10,15,18,90 These number go into 90 evenly
The six times tables are any and all multiples of 6. Therefore, any numbers that divide evenly by 6 will be in the six times tables, and any that don't won't be. 90/6 = 15, and so 90 does divide evenly by 6. Thus, 90 is in the six times tables.
1, 2, 4, 5, 10, and 20 divide evenly into 20.
These are the numbers that divide into 28 evenly: 1, 2, 4, 7, 14, 28.
They are called factors or divisors.
divisors
Sum them : 340 Count them: 4 numbers Divide sum by number of numbers = 340/4 = 85. Alternatively, in this case, you may notice that the numbers are evenly spaced. The middle two numbers are 80 and 90 so halfway between then will be the overall mean. This only works for the arithmetic mean of evenly spaced numbers.
1 and 19.
1 and 13