The weight of $72$ books is $9 \mathrm{kg}$. what is the weight of $40$ such books? 

Raju purchases $10$ pens for $₹150$ and Manish buys $7$ pens for $₹84.$ Can you say who got the pens cheaper?

Solve the following:

Anish made $42$ runs in $6$ overs and Anup made $63$ runs in $7$ overs. Who made more runs per over?

A bulb costs $₹120$. How many such bulbs can be bought for $₹1440$?

Weight of $8$ bags of sugar is $400 \mathrm{kg}$. The weight of $30$ such bags is _____.

The ratio of the number of boys to the number of girls in a school activity is $3:4$. There are $18$ more girls than boys. If $6$ boys quit, what will be the new ratio of the number of boys to the number of girls?

The simplest ratio of $200 \mathrm{g}$ and $1 \mathrm{kg}$ is _____.