Question

Round the number 45 to 1 significant figure
A) 45
B) 46
C) 40
D) 50

Answer 1

50 because when there is 5 in last then preceding digit would change into even no.

Answer 2

On rounding the number 45 to 1 significant figure, we get 50. (Option D)

• Rounding off to 1 significant figure means to round the figure at the unit's place.
• If the digit at the unit's place is 5 or greater, the digit at the tens place is increased by one.
• If it is less than 5, the digit at the unit's place is reduced to zero.
• Here, the unit's digit is 5. So, 4 will be increased by 1. The number becomes 50.