(a) Let the share of Sunil and Sumant be ₹ x and ₹ y, respectively.
∴ Share of Surat = ₹ [7700 - (x + y)]
According to the question,
=
=
⇒ 5x = 10y = [7700 - (x + y)) 15 [∵ r = 5%]
Equating first two, we get x = 2y
Now, 5x = [7700 - (x + y)] 15
⇒ 5 × 2y = [7700 - (2y + y)]15
⇒ 10y = 115500 -30 y - 15 y
⇒ 115500 = 55y ⇒ y = 2100
∴ x = 2y = 2 × 2100 = 4200
So, share of Surat
= 7700 - (x + y)
= 7700 - (4200 + 2100)
= 7700 - 6300 = ₹ 1400
Hence, required difference
= 4200 - 1400 = ₹ 2800