Total wages for a work is ₹ 1280. A alone can do a piece of work in 8 days, while B alone can do it in 12 days. If A and B work on alternate days, then find the share of A.

Work for 1 st 2 days = (1/8) + (1/12) = 5/24
∴ Work for 8 days = (5/24) x (8/2) = 5/6
∴ Remaining work = 1- (5/6) = (6 - 5) / 6 = 1/6
On 9th day, A's work = 1/8
Remaining work after 9 days = (1/6) - (1/8) = (4 - 3) / 24 = 1/24
B will finish this work in (12 x 1)/24 = 1/2 day
Clearly, A worked for 5 days from starting.
∴ Work done by A in 5 days = (1/8) x 5 = 5/8
∴ A's share = (5/8) x 1280 = 5 x 160 = ₹ 800