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3 years ago

The 6th term of an arithmetic progression is 35 and the 13th term is 77. find the 20th term

Mathematics

1 answer:

Helga [31]3 years ago

5 0

20th term= 119

Step-by-step explanation:

Let the first term of AP be a

and common difference be d

nth term is given by,

= a+(n-1)d

6th term = 35

a+(6-1)d= 35

a+5d=35 -----------------(i)

13th term = 77

a+12d= 77----------------(ii)

Now, equation (ii) - (i)

a+12d-(a+5d)= 77-35

a+12d-a-5d= 42

7d=42

d=6

Now, from equation (i)

a= 35-5d= 35-5(6)= 35-30 = 5

20th term= a+19d= 5+19(6)= 119

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Answer/Step-by-step explanation:

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The frame is to cover 8 sides with the length equal to the length of the base and 4 sides with the length of the height.

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The 6th term of an arithmetic progression is 35 and the 13th term is 77. find the 20th term​

The 6th term of an arithmetic progression is 35 and the 13th term is 77. find the 20th term