UPSC Civil Services 2016 Prelims General Studies Paper II

Quantity of product to be completed =19000 Firm
production per day =1000−5% of 1000 =950
Firm production in 19 days =19000−5% of 1900
=19000−

5

100

×19000
=19000−950=18050
So, firm needs one extra day other than 19 days to complete the order.
∴ Firm will complete the order in 20 days.