Question

Q10 : To what decimal place should each answer be rounded? How many significant figures does the rounded answer have? A) 101 cm - 99.1 cm =1.9 cm (unrounded) After rounding, the number should be reported to the ( choose answer ) ( ones place ) or ( tenths place ) or ( hundredths place ) and thus has ( choose answer ) ( 1 sig fig ) or ( 2 sig fig ) or ( 3 sig fig ) B) 0.5 atm + 9.8 atm = 10.3 atm (unrounded) After rounding, the number should be reported to the ( choose answer ) ( ones place ) or ( tenths place ) or ( hundredths place ) and thus has ( choose answer ) ( 1 sig fig ) or ( 2 sig fig ) or ( 3 sig fig )

Answer 1

In addition and substraction, we round off the answer to the least number of digits in any number (after decimal)

101 cm - 99.1 cm = 1.9

So here there is no number after decimal in 101 so we will round off the answer as 2 cm [rounded to ones place]

so there is one significant number

b) 0.5 atm + 9.8 atm = 10.3

There is one digit, in each given number to be added, after decimal. so the answer will rounded off to one digit after decimal

so answer is 10.3 [Three significant number]