RD Sharma Solutions (Part - 2) - Ex-2.1, Fractions, Class 7, Math | RD Sharma Solutions for Class 7 Mathematics PDF Download

QUESTION 10:

What should be added to 

ANSWER 10:

Let x be the required fraction.
According to the question:

QUESTION 11:

Suman studies for  hours daily. She devotes  hours of her time for Science and Mathematics. How much time does she devote for other subjects?

ANSWER 11:

Suman studies for   hours daily. Therefore, we have 

She studies science and mathematics for   hours. Therefore, we have 

Time devoted to other subjects = Total study time −- Time devoted to science and mathematics  

QUESTION 12:

A piece of wire is of length  If it is cut into two pieces in such a way that the length of one piece is   what is the length of the other piece? 

ANSWER 12:

Let the length of second piece be x.
Total length of wire = Length of one piece + Length of second piece

QUESTION 13:

A rectangular sheet of paper is   wide. Find its perimeter. 

ANSWER 13:

Perimeter of rectangle = 2(length + width)

QUESTION 14:

In a "magic square", the sum of the numbers in each row, in each column and along the diagonal is the same. Is this a magic  square?

ANSWER 14:

Sum along columns and rows:

Since, all the sums in the square   are equal along rows,columns and diagonals,it is a magic square. 

QUESTION 15:

The cost of Mathematics book is Rs  and that of Science book is Rs   Which costs more and by how much? 

ANSWER 15:

Cost of mathematics book =

Cost of Science book = 

Thus, Mathematics book costs more.Difference in the cost of Mathematics and Science book =cost of Mathematics book−Cost of Science book 

So, Mathematics book costs more by Rs 

QUESTION 16:

(i) Provide the number in box  and also give its simplest from in each of the following: 

ANSWER 16: