Math, asked by hahshha, 1 year ago

find the sum of first 22 terms of an ap in which d =22 and a22 =149

Answers

Answered by prasannas92
21
This is the required answer if any doubts you are welcome to ask
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hahshha: thank you
prasannas92: welcome
hahshha: this is wrong i guess
hahshha: check it once
hahshha: the ans is given -1804
Answered by Anonymous
10

\bf\huge\boxed{\boxed{\bf\huge\:Hello\:Mate}}}




\bf\huge Let \:a\: be\: first\: term\: be\: a\: and\: d\: be\: Common\: difference




\bf\huge d = 7 \:and\: a_{22} = 149




\bf\huge => a + (n - 1)d = 149




\bf\huge => a + 21\times 7 = 149




\bf\huge => a = 149 - 147 = 2




\bf\huge Substitute n = 22 , a = 2\: and\: d = 7




\bf\huge S_{n} = \frac{N}{2} [2a + (n - 1)d]




\bf\huge S_{22} = \frac{22}{2}[2\times 2 + (22 - 1)7]




\bf\huge = 11(4 + 21\times 7)




\bf\huge = 11(4 + 147)




\bf\huge => 11\times 151 = 1661




\bf\huge Sum\:of\: first\:22\:term\:is\:1661





\bf\huge\boxed{\boxed{\:Regards=\:Yash\:Raj}}}



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