Consider the pattern shown below:
1
3 5
7 9 11
13 15 17 19
...
which number comes first in the 81st row?
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Consider the pattern shown below:
1
3 5
7 9 11
13 15 17 19
...
which number comes first in the 81st row?
hi
is it 6641?
NO...
:) James:)
I think the answer is "6481"
explanation
the last number of each row is obtained by a formula
row number* rownumber+the number of terms in prevoius row
eg 2nd row : 2*2+1=5 (5 is last number of sec row)
3rd row: 3*3+ 2=11(11 is the last number of third row)
4 th row 4*4+3 =19(19..................................fourth row)
....
....
80 th row 80*80+79=6479(6479...................80 th row)
therefore fiirst number is 6481
hope iam right?
bye
Good work buddy...
earlier i got the wrong answer
since i found the last number of 81st row
i did 81*81+80=6641.
thats where i did mistake
bye
:)