If the sum of three numbers in A.P., is | Class 11 Mathematics Chapter Sequence and Series, Sequence and Series NCERT Solutions

Question:

If the sum of three numbers in A.P., is 24 and their product is 440, find the numbers.

Answer:

Let the three numbers in A.P. be a – d, a, and a + d.

According to the given information,

(a – d) + (a) + (a + d) = 24 … (1)

⇒ 3a = 24

∴ a = 8

(a – d) a (a + d) = 440 … (2)

⇒ (8 – d) (8) (8 + d) = 440

⇒ (8 – d) (8 + d) = 55

⇒ 64 – d2 = 55

⇒ d2 = 64 – 55 = 9

⇒ d = ± 3

Therefore, when d = 3, the numbers are 5, 8, and 11 and when d = –3, the numbers are 11, 8, and 5.

Thus, the three numbers are 5, 8, and 11.

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Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

Read the question carefully and focus on the core concept being asked.
Reference examples and data from the chapter when answering questions about Sequence and Series.
Review previous year question papers to get an idea of how such questions may be framed in exams.
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Comments

Asif
2019-12-15 20:19:13

Thnx

Asif
2019-12-15 20:18:38

Thnx

Deekshitha
2019-09-04 18:24:24

Thank you it for solving the problem and helped me

Deekshitha
2019-09-04 18:24:01

Thank you it for solving the problem and helped me

KICCHA balaji
2019-03-12 23:10:08

Tq bro Usefullll

Nikhil
2019-03-04 14:58:14

Thanx

QAMAR
2016-11-17 12:23:41

HOW CAN WE TAKE NUMBER I MEAN ON WHICH BASES

Mabel
2016-01-17 00:57:58

I luv dis.. Its easier and explanatory. Thanks!

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Welcome to the NCERT Solutions for Class 11 Mathematics - Chapter . This page offers a step-by-step solution to the specific question from Excercise 5 , Question 2: If the sum of three numbers in A.P., is 24 and their product is 440, find the numbers.....

If the sum of three numbers in A.P., is | Class 11 Mathematics Chapter Sequence and Series, Sequence and Series NCERT Solutions

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