15,21,57, _ ,221 reasoning question h plzz solve sir
Answers
Answered by
25
First thing first you missed one coma
Questions will be
1, 5, 21, 57, _, 221
Now see
arithematic progression
2², 4², 6², 8², 10²
4, 16, 36, 64, 100
1+4 = 5
5+16 = 21
21+36 = 57
57+64 = 121
121+100 = 221
So answer will be 121
Questions will be
1, 5, 21, 57, _, 221
Now see
arithematic progression
2², 4², 6², 8², 10²
4, 16, 36, 64, 100
1+4 = 5
5+16 = 21
21+36 = 57
57+64 = 121
121+100 = 221
So answer will be 121
Answered by
12
This series is like 1,5,21,57,..........,221
there is difference of 4, 16, 36 which are squres of 2,4,6 respectively.
So next difference will be square of 8=64 so 57+64=121 is the missing number in the series. 1,5,21,57,121,221
there is difference of 4, 16, 36 which are squres of 2,4,6 respectively.
So next difference will be square of 8=64 so 57+64=121 is the missing number in the series. 1,5,21,57,121,221
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