Due to a price hike of $20 \%$, $4 \text{ kg}$ less sugar is available for $₹ 120$. What is the initial price per kg of sugar (in $\text{ per kg}$)?

Suresh gave $40 \%$ of his income to his wife. He gave $25 \%$ of the remaining amount to his son. Of the remaining amount,he spent $60 \%$ on education. Now,the amount with him is $₹ 2700$. What is the amount he gave to his wife?

$A$ number is decreased by $10 \%$ and then increased by $10 \%$. The number so obtained is $10$ less than the original number. What was the original number?

The percentage increase in the surface area of a cube when each side is doubled is:

Aditya's salary is $125\%$ of Ram's salary. Sanjay's salary is $80\%$ of Ram's salary. If the total of all the three salaries is $Rs. 61000$,what is Sanjay's salary?

In an examination,there are $1000$ boys and $800$ girls. $60 \%$ of boys and $40 \%$ of girls passed. The percentage of candidates that failed is: (in $\%$)