find the next 2, 6, 21, 110, 777 plese somebody help me
Answers
Step-by-step explanation:
Method 1 :
The series can also be be written as
2 = 1 x 2,
6 = 2 x 3,
12 = 3 x 4,
20 = 4 x 5,
30 = 5 x 6 …….
nth number is “ n x (n+1) “
and hence the next number is
6 x 7 = 42 (Answer)
Method 2 :
The series can also be be written as
starts with 2
6 - 2 = 4 = (2 x 2)
12 - 6 = 6 = (2 x 3)
20 - 12 = 8 = (2 x 4)
30 - 20 = 10 = (2 x 5) …….
equation for nth number “ X “ is
“ X - previous value of (n-1) = ( 2 x n ) “
and hence the next number is
X - 30 = ( 2 x 6)
X = 30 + 12 = 42 (Answer)
Method 3 :
The series can also be be written as
starts with 2
2 nd digit is 6 = 2+ 4 = 2 + (2 x 2)
3 rd digit is 12 = 6 + 6 = 6 + (2 x 3)
4 th digit is 20 = 12 + 8 = (2 x 4)
5 th digit is 30 = 20 + 10 = 20+ (2 x 5) …….
nth digit is equal to “ previous value of (n-1) + ( 2 x n ) “
and hence the next 6 th number in series is 30 + ( 2 x 6) = 42 (Answer)