Find sum of all no. From 50 to 25o are divisible by 6 find t13
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Answered by
0
Smallest no.which is divisble by 6=54
largest no.=348
No.of terms in the AP=no.of the last term
a+(n-1)d=348
54+(n-1)6=348
(n-1)6=348-54=294
n-1=294/6=49
n=49+1=50
Sn=n/2(2a+(n-1)d)
=50/2(2(54)+49(6))
=25(108+294)
=25(402)
=10030
a15=54+14(6)
=54+84
=138.
hope it helps you.....
largest no.=348
No.of terms in the AP=no.of the last term
a+(n-1)d=348
54+(n-1)6=348
(n-1)6=348-54=294
n-1=294/6=49
n=49+1=50
Sn=n/2(2a+(n-1)d)
=50/2(2(54)+49(6))
=25(108+294)
=25(402)
=10030
a15=54+14(6)
=54+84
=138.
hope it helps you.....
Answered by
1
the no. between 50 to 250 and divisible by 6 are 54,60,66,72,78,84,90,96,102,108,114,120,126,132,138,144,150,156,162,168,174,180,186,192,198,204,210,216,222,228,234,240,246
so the 13th term is 126
by AP method
a=54 & d=6
13th term =a+12d=54+12*6=54+72=126
so the 13th term is 126
by AP method
a=54 & d=6
13th term =a+12d=54+12*6=54+72=126
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