Question

The number of significant figures in 0.00980, 12.345 x 10 and (2.5 x 10 + 25x10 are 3,5, 2 b) 3, 2, 5, 53, 2 d) 7,2, 3.​

Answer 1

Answer:

The number of significant figures in

0.00980  is 3

12.345 x 10 is 5

and

(2.5 x 10 + 25x10  is 2

Hence the solution is  3,5, 2

Explanation:

The rules for identifying significant figures when writing or interpreting numbers are as follows:

All non-zero digits are considered significant. For example, 91 has two significant figures (9 and 1), while 123.45 has five significant figures (1, 2, 3, 4 and 5).

Zeros appearing anywhere between two significant figures are significant: 101.1203 has seven significant figures: 1, 0, 1, 1, 2, 0 and 3.

Zeros to the left of the significant figures (leading zeros) are not significant. For example, 0.00052 has two significant figures: 5 and 2.

Zeros to the right of the non-zero digits (trailing zeros) are significant if they are to the right of the decimal point as these are only necessary to indicate precision. However trailing zeros in the ones place or higher may or may not be significant, depending on the precision of the measurement. Thus 1.20 and 0.0980 have three significant figures whereas 45,600 may have 3, 4 or 5 significant figures. Note that 120.00 would have five significant figures - the zero to the left of the decimal is significant because it is between two significant figures (the 2 and the zeros to the right of the decimal point).

Hope it helps