The mass of a gold coin was measured three times and each measurement was made to five digits. The mass values were 23.319g, 23.341 g, and 23.296g. the average mass was reported as 23.32 g. The actual mass of the coin is 25.5631g.
Why is the average mass of the gold coin reported to only four significant figures?
1 answer
Looking at 23.319, the 233 and 1 are known but the last number is uncertain. The average is 23.3198 which rounds to 23.320 but the 0 is in the uncertain column so it is reported as 23.32.