Question 2

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)

⇒ 3*a* = 24

∴ *a* = 8

(*a* – *d*) *a* (*a* + *d*) = 440 … (2)

⇒ (8 – *d*) (8) (8 + *d*) = 440

⇒ (8 – *d*) (8 + *d*) = 55

⇒ 64 – *d*2 = 55

⇒ *d*2 = 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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The sum of the first four terms of an A.P. is 56. The sum of the last four terms is 112. If its first term is 11, then find the number of terms.

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^{2}, 3^{3}, … are needed to give the sum 120? - Q:-
Find the sum of all numbers between 200 and 400 which are divisible by 7.

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(i) A = {x: x is an integer and - 3 < x < 7}.

(ii) B = {x: x is a natural number less than 6}.

(iii) C = {x: x is a two-digit natural number such that the sum of its digits is 8}

(iv) D = {x: x is a prime number which is divisor of 60}.

(v) E = The set of all letters in the word TRIGONOMETRY.

(vi) F = The set of all letters in the word BETTER. - Q:-
Insert five numbers between 8 and 26 such that the resulting sequence is an A.P.

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The 4th term of a G.P. is square of its second term, and the first term is –3. Determine its 7th term.

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Insert two numbers between 3 and 81 so that the resulting sequence is G.P.

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The sum of the first four terms of an A.P. is 56. The sum of the last four terms is 112. If its first term is 11, then find the number of terms.

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A man starts repaying a loan as first installment of Rs. 100. If he increases the installment by Rs 5 every month, what amount he will pay in the 30th installment?

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Find the derivative of x

^{2}– 2 at x = 10. - Q:-
Insert five numbers between 8 and 26 such that the resulting sequence is an A.P.

- Q:-
If the sum of first p terms of an A.P. is equal to the sum of the first q terms, then find the sum of the first (p + q) terms.

- Q:-
A coin is tossed. If it shows a tail, we draw a ball from a box which contains 2 red and 3 black balls. If it shows head, we throw a die. Find the sample space for this experiment.

- Q:- In an A.P, the first term is 2 and the sum of the first five terms is one-fourth of the next five terms. Show that 20th term is –112.
- Q:-
Evaluate

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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