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roUNDINg NUMbErS
The birthday of Sardar Vallabhbhai Patel,
the Iron Man of India, was celebrated as
National Unity Day at Blue Marble School.
About 50 students participated in the
‘Run for Unity’. NatioNal UNity
Day
Here, we use 50 as a rounded number. The 31 October
st
number 50 is close to the actual number. theme : RUN foR UNity
The actual number may be more or a little motto: Not me BUt yoU
less than 50.
rounding off to the Nearest 10
Example 1. Round off 54 to the nearest 10.
Solution. We can use a number line to round 54. Look at the given number line in
tens.
54
10 20 30 40 50 60 70
We can see that 54 lies between 50 and 60, but closer to 50 than 60. So, 54 rounds
to 50.
Example 2. Round off 37 to the nearest 10.
Solution. Study the number line below:
37
10 20 30 40 50 60 70
The number 37 lies between 30 and 40, but closer to 40 than 30. So, 37 rounds to 40.
Example 3. Round off 45 to the nearest 10.
Solution. Look at the given number line.
45
10 20 30 40 50 60 70
45 is exactly midway between 40 and 50. So, 45 rounds to 50.
30 Mathematics 3
