when we do convertions, do we have follow the rules for rounding?
is it 118.5cm=1.19m, or 118.5cm=1.18m?
It depends upon how many significant figures (sf) you are allowed, whether you are doing converSions or calculating some other problem. By definition, there are 100.000000000 cm in 1.00000000000 meter; therefore, 118.5 cm = 1.185 m. You have 4 sf in 118.5 and you are allowed to have 4 in the answer.
the precision of the stopwatch is 0.01second, if the question ask us to provide the answer to the nearest 0.1second,so...
12.65seconds=12.6 or 12.7seconds?
Some people do rounding differently when the last number is a 5. I follow the rule to "round to the even number." Therefore, I would round to 12.6 since 6 is the even number. If it were 12.75, I would round to 12.8 (the nearest even number). I hope this helps.
When it comes to rounding, there are different rules and conventions that can be followed. It is important to be consistent and follow the specific rules or guidelines given in the problem or context.
In the case of the conversion from centimeters to meters, if you are asked to round to two decimal places, then 118.5 cm would be rounded to 1.19 m. This is because the number after the second decimal place, which is 5, is rounded up to the next higher number.
However, if you are asked to round to one decimal place, then 118.5 cm would be rounded to 1.2 m. In this case, the number after the first decimal place is 5, which also rounds up to the next higher number.
Ultimately, it is important to follow the specific rules or guidelines given in the problem or context to ensure accurate rounding.