If sum of four consecutive numbers in an AP is 32 the ratio of the pro...
Here mine ans is..2,6,10..and 14..as told by manoj u will get a=8..an a.c..to further condition..you will get d=2..
If sum of four consecutive numbers in an AP is 32 the ratio of the pro...
Explanation:
Given:
Sum of four consecutive numbers in an AP is 32.
The ratio of the product of the first and the last term to the product of two middle terms is 7:15.
Let's assume the four consecutive numbers in the AP are:
a, a + d, a + 2d, a + 3d
Sum of the four consecutive numbers:
a + (a + d) + (a + 2d) + (a + 3d) = 32
4a + 6d = 32
2a + 3d = 16
Product of the first and the last term:
a * (a + 3d)
Product of the two middle terms:
(a + d) * (a + 2d)
Ratio of the products:
(a * (a + 3d)) / ((a + d) * (a + 2d)) = 7 / 15
(a^2 + 3ad) / (a^2 + 3ad + 2d^2) = 7 / 15
15a^2 + 45ad = 7a^2 + 21ad + 14d^2
8a^2 + 24ad - 14d^2 = 0
2a^2 + 6ad - 3d^2 = 0
Solving the equations:
2a^2 + 6ad - 3d^2 = 0
a(2a + 3d) - d(2a + 3d) = 0
(a - d)(2a + 3d) = 0
a = d or a = -1.5d
Since the numbers are positive, a = d
Substitute back into 2a + 3d = 16
2d + 3d = 16
5d = 16
d = 3.2
Therefore, the four consecutive numbers are:
a = 3.2, a + d = 6.4, a + 2d = 9.6, a + 3d = 12.8
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