If 5 × A = CA then the values of A and C are
(a) A = 5, C = 1
(b) A = 4, C = 2
(c) A = 5, C = 2
(d) A = 2, C = 5

Solution:

If 5 × A = CA implies that when 5 is multiplied by A it gives A in the units place.

We know that when 1 or 5 or 6 is multiplied by themselves they give the same digit in the resulting number.

In this case since A is multiplied by 5 implies that A has to be 5.

5 × A = CA

5 × 5 = 25

Therefore C = 2 and A = 5

CA = 25

The correct choice is (c ) .

✦ Try This: If 6 × A = CA then the values of A and C are (a) A = 6, C = 3 (b) A = 6, C = 4 (c) A = 4, C = 2 (d) A = 2, C = 1

In the given problem A can take three values:

A can be 6, 4 and 2

6 × A = CA

6 × 6 = 36 One of the correct option is A = 6; C = 3

6 × 4 = 24 The other correct option is A = 4; C = 4

6 × 2 = 12 The other correct option is A = 2; C=1

The correct options are (a), (b) and (d)

☛ Also Check: NCERT Solutions for Class 8 Maths Chapter 16

NCERT Exemplar Class 8 Maths Chapter 13 Sample Problem 3

If 5 × A = CA then the values of A and C are (a) A = 5, C = 1 (b) A = 4, C = 2 (c) A = 5, C = 2 (d) A = 2, C = 5

Summary:

If 5 × A = CA then the values of A and C are 5 and 2 respectively.

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