Math, asked by sunidhi28, 1 year ago

please solve question number 13 ​

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Answered by manthan7445
2

Given

First term = a = 12

Let the 7th term = a + 6d = 12 + 6d

and 11th term = a + 10d = 12 + 10d

Given that 7th term is 24 less than 11th term

then the equation will be

12 + 6d = 12 + 10d - 24

-4d = -24

d = 6

Now d = 6 a = 12

Tn = a +( n - 1)d

T20 = 12 + (20 - 1)6

T20 = 12 + (19)×6

T20 = 12 + 114 = 126

Thus the 20th term of A.P is 126

Answered by Anonymous
3

Here is your answer mate

⤵⤵

Let the 7th term be a7 and 11th term be a11 ,

where a1(1st term) =12

a11 -a7 = 24

(a+ 10d) - (a+6d) = 24

a +10d - a -6d =24

4d =24

hence,d= 6

now 20th term, a20 = a+19d

= 12+ 114 = 126......ans.

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