Synopsis IAS

Answer

Solution

UPSC Prelims

Mathematics

Theme:

Number System / संख्या पद्धति

Q11 2020, Number System

In the sum +1+58+8+1=188 for which digit does the symbol & stand?

Let ® = x,

Then,

x + 1x + 5x + xx + x1 = 1xx …(i)

Concept: write the numbers in the form of their place value.

Using (i), we have,

x + (10 + x) + (50 + x) + (10x + x) + (10x + 1) = 100 + 10x + x

=>24x + 61 = 100 + 11x

=>13x = 39

=> x = 3 Hence, ® = 3

Q 11. 2020, Number System