25 and 50
7,14,21,28,35,42,49,56 & 63
25, 50, 75, 100, 125.
They are: 25 50 75 100 and 125
The multiples of 25 are 1, 5, and 25.
The first two multiples are 9 and 8.
What about them?
25 and 50
The sum of the first 25 numbers is 25*26/2 = 325 So the sum of the first 25 multiples of 12 is 325*12 = 3900
7,14,21,28,35,42,49,56 & 63
The highest power of 25 that divides the product of the first 100 multiples of 5 is 50. This is because for each multiple of 25, we have an extra factor of 25. Since there are 4 multiples of 25 in the first 100 multiples of 5, we have a total of 50 factors of 25.
9, 18, 27
It is 75.
25, 50, 75, 100
The first four multiples of five: 5, 10, 15, 20
36, 72, 108
72 and 144