CBSE NCERT Solutions for Class 8 Chapter 16

NCERT Solutions clear concepts ensuring to stay with students in exams. Students will find it extremely easy to understand Math problems and how to go about solving them. NCERT Solutions are prepared by experts to provide accurate and easy solutions for all questions covered in class 8.

CBSE NCERT Solutions for Class 8 Maths Chapter 16:

Question-1:

If 21y^5 is a multiple of 9, where y is a digit, what is the value of y?

Solution:

Since 21y5 is a multiple of 9.
Therefore according to the divisibility rule of 9, the sum of all the digits should be a multiple of 9.
Therefore, 2+1+y+5=8+y
8y-= 9
y = 1
This is possible when 8+y is any one of these numbers 0, 9, 18, 27, and so on .......
However, since y is a single digit number, this sum can be 9 only. Therefore, y should be 1 only.

Question-2:

If 31z5 is a multiple of 9, where z is a digit, what is the value of z? You will find that there are two answers for the last problem. Why is this so?

Solution:

Since, 31z5 is a multiple of 9.
Therefore according to the divisibility rule of 9, the sum of all the digits should be a multiple of
9.
Therefore, 3+1+z+5=9+z
9 +z=9
z =0
If 3+1+z+5=9+z
Hence 0 and 9 are two possible answers.

Question-3:

Find the value of the following letters.
numbers

Solution:

Here, we observe that B = 5 so that 7 + 5 =12.
Putting 2 at ones place and carry over 1 and A = 2, we get
2 + 3 + 1 =6
Hence A = 2 and B =5