Question

divide 28 into four parts in an arithmetic progression so that the ratio of the product of first and third with the product of second and fourth is 8:15

Answer 1

Step-by-step explanation:

Here 4a=28 So a=7.

Also

(a−d)(a+3d)

(a−3d)(a+d)

=

15

8

15[a

2

−3d

2

−2ad]=8[a

2

−3d

2

+2ad]

7[a

2

−3d

2

]=46ad

7(49−3d

2

)=46×7.d

49−3d

2

=46d

3d

2

+46d−49=0

(d−1)(3d+49)=0

d=1

Required numbers are 4,6,8,10