Math, asked by 8822768811, 1 year ago

The sum of four consecutive number in AP is 32 and the ratio of the product of the first and the last term to the product of two middle tem is 7:5.find the numbers

Answers

Answered by Zainab1283
4
Let, the four consecutive numbers are
(a - 3d), (a - d), (a + d) and (a + 3d).

Given that,

(a - 3d) + (a - d) + (a + d) + (a + 3d) = 32

=> 4a = 32

=> a = 8

So, the numbers are

(8 - 3d), (8 - d), (8 + d) and (8 + 3d).

Given that :

(8 - 3d)(8 + 3d) : (8 - d)(8 + d) = 7 : 15

=> (64 - 9d²) : (64 - d²) = 7 : 15

=> (64 - 9d²)/(64 - d²) = 7/15

=> 960 - 135d² = 448 - 7d²

=> 128d² = 512

=> d² = 4

So, d = ± 2.

So, the numbers are :

2, 6, 10, 14

or,

14, 10, 6, 2.

Therefore, the four consecutive numbers are

2, 6, 10, 14

Read more on Brainly.in - https://brainly.in/question/3098427#readmore

Imzan: can you please explain how did you take the terms as a-3d a-d a+d a+3d ?
Zainab1283: yes
Zainab1283: a is the first term of an AP
8822768811: Why not taken a-d,a,a+d,a+2d instead of that ?
Answered by abhijithdethp63g10
1
RATIO IS 7:15

Let, the four consecutive numbers are(a - 3d), (a - d), (a + d) and (a + 3d).
Given that,
(a - 3d) + (a - d) + (a + d) + (a + 3d) = 32
=> 4a = 32
=> a = 8
So, the numbers are
(8 - 3d), (8 - d), (8 + d) and (8 + 3d).
Given that :
(8 - 3d)(8 + 3d) : (8 - d)(8 + d) = 7 : 15
=> (64 - 9d²) : (64 - d²) = 7 : 15
=> (64 - 9d²)/(64 - d²) = 7/15
=> 960 - 135d² = 448 - 7d²
=> 128d² = 512
=> d² = 4
So, d = ± 2.
So, the numbers are :
2, 6, 10, 14
or,
14, 10, 6, 2.
Therefore, the four consecutive numbers are
2, 6, 10, 14.

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