Question

Rakhi works in a store which offers the following forms of payment :

Get ₹5 on the first day, ₹10 on the second day, 15th on the third and so on. 
Get ₹540 per month. 

If she works for only 10 days,  which mode of payment she must choose? 

Answer 1

she must choose .1st way because it will give him more benefit.

i.e.......

5+10+15+....+50 = (10/2)[2*5+(10-1)5] = 5*55= 275