$A$ man sells two articles,each for $Rs. 640$. He earns $20\%$ profit on the first and $40\%$ profit on the second. Find his overall percent profit.

$A$ shopkeeper cheats to the extent of $10 \%$ while buying as well as selling by using false weights. His total gain percentage is:

An electric pump was sold at a profit of $15 \%$. Had it been sold for $Rs. 600$, the profit would have been $20 \%$. What was the former selling price in $Rs.$?

$A$ shopkeeper bought $30\, Kg$ of wheat at the rate of $Rs.\, 45$ per $Kg$. He sold $40\%$ of the total quantity at the rate of $Rs.\, 50$ per $Kg$. Approximately,at what price per $Kg$ should he sell the remaining quantity to make $25\%$ overall profit? (in $Rs.$)

Find $SP$ when $CP = Rs. 80.40$ and $\text{loss} = 5\%$.

If a vendor sells a coconut at $Rs. 14.4$,he makes a $10 \%$ loss. If he wants to make a $25 \%$ profit,at what price (in $Rs.$) should he sell it?