It is part of the series known as the triangular numbers.
21: (3)+3=(6)+4=(10)+5=(15)+6=(21)
To find the missing number in the sequence 10, 15, 28, we can look for a pattern in the differences between the numbers. The difference between 10 and 15 is 5, and the difference between 15 and 28 is 13. If we assume a pattern in the differences, the missing number could be 21, which fits as the average of 15 and 28. Thus, the sequence could be 10, 15, 21, 28.
5/7 - 5/21 = 15/21 - 5/21 = 10/215/7 - 5/21 = 15/21 - 5/21 = 10/215/7 - 5/21 = 15/21 - 5/21 = 10/215/7 - 5/21 = 15/21 - 5/21 = 10/21
The difference increases by one. 3, 6, 10, 15, 21, 28, 36 and so on.
7/10 of 15 = 15*7/10 = 21/2
21: (3)+3=(6)+4=(10)+5=(15)+6=(21)
To find the missing number in the sequence 10, 15, 28, we can look for a pattern in the differences between the numbers. The difference between 10 and 15 is 5, and the difference between 15 and 28 is 13. If we assume a pattern in the differences, the missing number could be 21, which fits as the average of 15 and 28. Thus, the sequence could be 10, 15, 21, 28.
5/7 - 5/21 = 15/21 - 5/21 = 10/215/7 - 5/21 = 15/21 - 5/21 = 10/215/7 - 5/21 = 15/21 - 5/21 = 10/215/7 - 5/21 = 15/21 - 5/21 = 10/21
The difference increases by one. 3, 6, 10, 15, 21, 28, 36 and so on.
They are 6, 10, 14, 15, 21, 22.They are 6, 10, 14, 15, 21, 22.They are 6, 10, 14, 15, 21, 22.They are 6, 10, 14, 15, 21, 22.
7/10 of 15 = 15*7/10 = 21/2
Points: (6, -10) and (-15, 15) Slope: (-10-15)/(6--15) = -25/21
25 + 15 + 21 + 10 + 11 = 82
Catch 21 - 2008 2009-10-15 was released on: USA: 15 October 2009
Yes. 15*(2/3) = 10 and 21*(2/3) = 14
10 and 21
21-28-36-45-55-66-74-87-101