5 + 10+15+20=50 ans
6+12+18+24+30=90
3+6+9...+45taking 3 common3(1+2+...+15) = 360
6 + 12 + 18 + 24 + 30 + 36 = 126
The first 6 multiples of 9 are 9, 18, 27, 36, 45 and 54. Their sum (total) is 189. In other words, 1x9 + 2x9 + 3x9 + 4x9 + 5x9 + 6x9 = 21x9 = 189.
90
5 + 10+15+20=50 ans
It is: 6+12+18 = 36
The sum of three consecutive multiples of 6 is 666, the multiples are 216, 222 and 228.
6+12+18+24+30=90
3+6+9...+45taking 3 common3(1+2+...+15) = 360
6 + 12 + 18 + 24 + 30 + 36 = 126
First three common multiples of 2 and 6 are 6, 12 and 18.
0, 2, 4, 6, 8.0,2,4,6,8 are the first five multiples of 2
6 and 12.
2
The first 6 multiples of 9 are 9, 18, 27, 36, 45 and 54. Their sum (total) is 189. In other words, 1x9 + 2x9 + 3x9 + 4x9 + 5x9 + 6x9 = 21x9 = 189.