CSATNumber System & SeriesDigits Arithmetic2019

The ratio of a two-digit natural number to a number formed by reversing its digits is 4 : 7. The number of such pairs is

A

5

B

4

C

3

D

2

Correct Answer: Option B

Explanation

1. **Recall PYQ Context**: From analyzing 2017 Question 73 and 79, we know the standard way to handle 'two-digit nu

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