123. P can complete a work in 12 days working 8 hours a day. Q can complete the same work in 8 days working 10 hours a day. If both P and Q work together, working 8 hours a day, in how many days can they complete the work?

✅ The correct answer is option A.
P can complete the work in (12 x 8) hrs. = 96 hrs.
Q can complete the work in (8 x 10) hrs. = 80 hrs.

P’s1 hour’s work =
1
and Q’s 1 hour’s work =
1
.

96
80

(P + Q)’s 1 hour’s work =

1
+
1

=
11
.

96
80
480

So, both P and Q will finish the work in

480

hrs.

11

Number of days of 8 hours each =

480
x
1

=
60
days = 5
5
days.

11
8
11
11