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Question: Divide 24 in three parts such that they are in AP and their product is 440....

Divide 24 in three parts such that they are in AP and their product is 440.

Explanation

Solution

As given in the question the three parts are in AP then let the three parts of 24 is ad,a,a+da - d, a, a + d. Then submission of all three parts is equal to 24 from here we will calculate a. then the product of three parts is 440 from this we will calculate d.

Complete step by step solution:
Given three parts of 24 is in AP then let us assume three numbers to be ad,a,a+da - d, a, a + d
So, ad+a+a+d=24a - d + a + a + d = 24
Therefore a=8a = 8
Now, product of all three parts are 440 then
(ad)×(a)×(a+d)=440\left( {a - d} \right) \times \left( a \right) \times \left( {a + d} \right) = 440
Substituting a=8a = 8
(8d)×(8)×(8+d)=440\left( {8 - d} \right) \times \left( 8 \right) \times \left( {8 + d} \right) = 440
We know that a2b2=(ab)(a+b){a^2} - {b^2} = \left( {a - b} \right)\left( {a + b} \right)
(82d2)=55\left( {{8^2} - {d^2}} \right) = 55
d2=6455=9{d^2} = 64 - 55 = 9
Taking root on both side we get
d=3d = 3

So, three parts of 24 are 5, 8, 11.

Note:
For consecutive three terms to be in AP ad,a,a+da - d,a,a + d
For 4 consecutive terms in AP =a2d,ad,a+d,a+2da - 2d,a - d,a + d,a + 2d and so one …
Where a is the 1st term of AP and d is the common difference