O P Malhotra, S K Gupta and, Anubhuti Gangal Solutions for Chapter: Unitary Method and Time and Work, Exercise 1: Exercise

The weight of $45$ books is $9 \mathrm{kg}$. How many books will weight $10.8 \mathrm{kg}$.

$15$ boxes each containing $18$ juice cartons cost $₹5400$. What is the cost of $22$ boxes each containing $14$ juice cartons?

$28$ pumps can empty a reservoir in $18$ hours. In $k \mathrm{hrs}$ can $42$ such pumps do the same work. Find the value of $k$.

A contractor who had a workforce of $630$ persons undertook to complete a portion of a stadium in $14$ months. He was asked to complete the job in $9$ months. How many extra persons had he to employ?

A hostel had rations for $60$ days for $500$ students. After $12$ days, $300$ more students join the hostel mess. If the remaining ration last for $k$ days, find the value of $k$

A man travels a certain distance by train in $4$ hours and $12$ minutes at the speed of $44.8$ $\mathrm{km}$ per hour. When the speed of the train is increased to $58.8$ $\mathrm{km}$ per hour, then the time taken to cover the same distance is $k$ minutes. Find the value of $k$.

A besieged town has provisions to last for $3$ weeks. Its population is $22400.$ How many people must be sent away in order that the provisions may last for $7$ weeks?

It is found that a book will contain $350$ pages, if $32$ lines are allowed in a page. How many lines should be allowed in a page, if the book is to contain $280$ pages?