The numbers 2.745 and 2.735 on rounding off to 3 significant figures will give:
a) 2.75 and 2.74
b) 2.74 and 2.73
c) 2.75 and 2.73
d) 2.74 and 2.74
The numbers 2.745 and 2.735 on rounding off to 3 significant figures will give:
a) 2.75 and 2.74
b) 2.74 and 2.73
c) 2.75 and 2.73
d) 2.74 and 2.74

Correct answer is d) 2.74 and 2.74

By convention, we apply the following criteria for rounding off measurements:
1. If the dropped digit is less than 5, the preceding digit remains unaffected.
2. If the dropped digit is greater than 5, the preceding digit is increased by one.
3. The preceding digit is raised by one if the digit to be eliminated is 5 followed by digits other than zero.
4. If the preceding digit is even and the digit to be eliminated is 5 or 5 followed by zeros, the preceding digit is left unmodified.
5. If digit to be dropped is 5 or 5 followed by zeros, then the preceding digit is raised by one, if it is odd.
Hence on rounding off 2.745, it would be 2.74.
Consider 2.737; the digit to be eliminated is 5, and if the preceding digit is odd, it is raised by one. As a result, rounding off 2.735 to three significant digits yields 2.74.