Hi teacher,

The activities of the chapter 4,activity 4 i didn't understand how will get the answer?

I am explaining you the first part of activity as:

Here, we have to fill that number in the blank box which will make the corresponding fraction equivalent to the 2/3 or 10/15

Consider the first case:

Here, numerator is 2 on LHS and 6 on RHS.

We know that 6 = 3 × 2, i.e., on multiplying 2 by 3 we get 6.

Similarly, in denominator of LHS, we have 3. So, we also multiply it by 3 to get the denominator of corresponding fraction on RHS.

⇒ 3 × 3 = 9 

Therefore, 2/3 = 6/9

Similarly, we have

In the equivalent fraction 

We had 3 in denominator on LHS and 21 in denominator on RHS.

We know that on multiplying 3 with 7 we get 21.

So, we also multiply 2 with 7 to get the number in numerator on RHS.

Now, 2 × 7 = 14 

Therefore, 2/3 = 14/21

In the same manner, you can find the missing numbers for second part. 

 Hope you get it!!