A man buys an article for $10 \%$ less than its value and sells it for $10 \%$ more than its value. His gain or loss percent is
No profit, no loss
$20 \%$ profit
Less than $20 \%$ profit
More than $20 \%$ profit
An item costing $Rs.\, 200$ is being sold at $10 \%$ loss. If the price is further reduced by $5 \%,$ the selling price will be (in $Rs.$)
Surbhi bought a combined total of $25$ i-pads and i-phones. She marked up the i-pad by $20 \%$ on the cost price, while each i-phone was marked up by $Rs.\, 2000.$ She was able to sell $75 \%$ of the i-pads and $2$ i-phones and make a profit of $Rs.$ $49000 .$ The remaining i-pads and $3$ i-phones could not be sold by her. Find her overall profit or loss if she gets no return on unsold items and it is known that an i-phone costs $50 \%$ of an i-pad.
Mohan buys a watch for $Rs.\,350$ and sells it for $Rs.\,392.$ Find out his percentage of profit.
The cost price of $20$ articles is the same as the selling price of $x$ articles. If the profit is $25 \%$, then the value of $x$ is in $Rs.$
Present age of Bob is equal to Abby's age $8\, years$ ago. Four years hence, the respective ratio between Bob's age and Abby's age will be $4: 5$ at that time. What is Bob's present age? (in $years$)