Bayo borrowed 2000 naira from his friend. He agreed to pay it back after 2 years together with an interest of 2½% per 1 year. How much should he pay back to his friend?

1 answer

The interest per year is 2½% of 2000 naira which is equal to (2½/100)*2000 = <<(2.5/100)*2000=50>>50 naira.
The interest for 2 years is 50*2 = <<50*2=100>>100 naira.
Therefore, Bayo should pay back 2000+100 = <<2000+100=2100>>2100 naira. Answer: \boxed{2100}.