Question

What is 3,482 to two significant figures

Answer 1

Dear Student,

Solution:

To find significant figures for digit or tens digit

if last two digits are 50 or greater than 50,then add +1 to the hundredth digit and remove last two digits.

if lat two digits are less than 50 then no change in hundred th digit,last two numbers to be removed.

In 3,482 : last two digits are 82, 82> 50

So, number is 3500.

Hope it helps you.

Answer 2

So basically rounding off to significant figures is similar to rounding off to nearest 10's or decimal places of whole numbers.

Solution:

Look at if last two digits are 50 or greater than 50,then add +1 to the hundredth digit and remove last two digits.

if the last two digits are less than 50 then no change in the hundred'th digit,thus the last two numbers have to be removed.

In 3,482 : last two digits are 82. 82 is more than 50, so the last two will turn 00 and +1 will be added.

So, number increases and becomes 3500.

For your understanding its important to know what main rules apply.

TIP:

-The first significant figure of a number is the first digit which is not zero. Hence the first significant figure of 20,499 is 2 and the first significant figure of 0.0020499 is 2.

-The second significant figure of a number is the digit after the first significant figure. This is true even if the digit is zero. Hence the second significant figure of 20,499 is 0, similarly, the second significant figure of 0.0020499 is also 0.

Next step:

We round a number to 2 significant figures in the same way that we would round to 2 decimal places. We count from the first non-zero digit for three digits. We then round the last digit. We fill in any remaining places to the right of the decimal point with zeros. This is because we need them to hold the correct place value for the significant digits.