Meenu bought two fans for Rs 1200 each. She sold one at a loss of 5% and the other at a profit of 10%. Find out the total profit or loss.

Given, 

the cost price of the first fan = Rs 1200
She sold the fan at a loss of 5%
⇒ Loss on the first fan= 5% of Rs 1200$=\frac{5}{100}\times 1200=\mathrm{Rs} 60$.
The selling price of the first fan = Cost price - loss = Rs 1200 - Rs 60 = Rs 1140

The cost price of 2nd fan = Rs 1200
She sold at a profit of 10%
Profit on the second fan= 10% of 1200 $=\frac{10}{100}\times 1200=\mathrm{Rs} 120$.
The selling price of the 2nd fan = profit + Cost price
= Rs 1200 + Rs 120 = Rs 1320

The total cost price of two fans = Rs 1200 + Rs 1200 = Rs 2400.
Total S.P of 2 fans = Rs 1320 + Rs 1140 = Rs 2460
Since S.P > C.P
She got a profit on the whole.
Profit = S.P - C.P = Rs 2460 - Rs 2400 = Rs 60.
$\mathrm{Profit}\%=\frac{\mathrm{Profit}}{\mathrm{Cost} \mathrm{price}}\times 100$

$\mathrm{Profit}\%=\frac{60}{2400}\times 100$
$\mathrm{Profit}\%=2.5\%$.