An amount of ₹ $70,000$ was lent at $6 \%$ per annum and the remaining at $4 \%$ per annum. If the total simple interest from both the fractions in $5 \text{ years}$ was ₹ $16,000$,the sum lent at $6 \%$ per annum was (in ₹). (in $,000$)

The ratio of alcohol and water in $40$ $litres$ of mixture is $5:3$. Then $8$ $litres$ of the mixture is removed and replaced with water. Now,the ratio of the alcohol and water in the resultant mixture is

$A$ shopkeeper bought $30 \text{ kg}$ of rice at the rate of $₹ 70$ per $\text{kg}$ and $20 \text{ kg}$ of rice at the rate of $₹ 70.75$ per $\text{kg}$. If he mixed the two brands of rice and sold the mixture at $₹ 80.50$ per $\text{kg}$,his total gain is (in $₹$):

$80 \text{ litre}$ mixture of milk and water contains $10 \%$ milk. How much milk (in $\text{litre}$) must be added to make water percentage in the mixture $80 \% ?$

In what ratio must a grocer mix two varieties of pulses costing $Rs. 15$ and $Rs. 20$ per $kg$ respectively so as to get a mixture worth $Rs. 16.5$ per $kg$?

In what ratio must water be added to spirit to gain $10 \%$ by selling it at the cost price?