Question

Calculate the following and show working, use accurate significant significant figures . How many cm is 485.0 inches ( 1 inch=2.54 cm).

Answer 1

If you're converting inches to cm, the number of significant digits is controlled by the inches. The 2.54 in cm/in is exact, so it doesn't enter into the choice of significant digits.

485.0in x (2.54 cm/in) = 1231.9 cm
In this case the number of significant digits is controlled by "485.0in".

so we our answer is 1231.9 so number of significant figure is 5

1) ALL non-zero numbers (1,2,3,4,5,6,7,8,9) are ALWAYS significant.
2) ALL zeroes between non-zero numbers are ALWAYS significant.
3) ALL zeroes which are to the right of the decimal point AND at the end of the number are ALWAYS significant.
4) ALL zeroes which are to the left of a written decimal point and are in a number >= 10 are ALWAYS significant