R S Aggarwal Solutions for Chapter: Unitary Method, Exercise 2: EXERCISE 9B

A girl can finish a book in $25 days$ if she reads $18 pages$ of it every day. How many days will she take to finish it, if she reads$15 pages$every day?

Reeta type$40 words$ per minute and takes$24 minutes$ to type a certain document. Her friend Geeta has a typing speed of $48 words$ per minute. In how much time, will she be able to type the same document?

A bus covers a certain distance in $3 \mathrm{hours} 20 \mathrm{minutes}$ at an average speed $45 \mathrm{km}/\mathrm{h}$. How long will it take to cover the same distance at a speed of $36 \mathrm{km}/\mathrm{h}$?

At the beginning of a month, a factory has enough materials to make $240 tonnes$ of steel in a month. If $60$ more tonnes of steel is to be made that month, how long will the materials last?

A contractor employed$210$ men to build a house in$60$ days. After $12$ days, he was joined by $70$ more men. In how many days will the remaining work be finished?

A military camp has provisions for $360$ men to last for $25$ days. How many men must be transferred to another camp so that the food lasts for $30$ days?

A group of $120 \mathrm{men}$ had provisions for $200 \mathrm{days}$. After$5 \mathrm{days}, 30 \mathrm{men}$ died due to an epidemic. How long will the remaining food last?

$1200$ soldiers in a fort had enough food for$28$days. After$4$ days, some soldiers were transferred to another fort and thus the food lasted for an extra $32 \text{days}$. How many soldiers left the fort?