NCERT Exemplar Solutions
Class 6 - Mathematics - Unit 1: Number System - Multiple Choice Questions

Question 10

We must keep the digit 6 exactly where it is, and only rearrange the other digits to make the whole number as small as possible.

Step 1: List the other digits: 3, 5, 0, 9, 4, 7.

Step 2: To get the smallest number, arrange these digits in increasing order (smallest first).

So we order them as: (0,;3,;4,;5,;7,;9).

Step 3: Put these digits after the fixed 6 in the same order. That gives:

(6;0;3;4;5;7;9)

Therefore the smallest number is 6034579, which is option C.