Question #29219

1 Answer
Stefan V.
Sep 17, 2017

Here's how you can do that.

Explanation:

In order to round your number off to two significant figures, you must compare the value of the third significant digit to #5#.

If the third significant digit is #>=5#, then you will add #1# to the value of the second significant digit and eliminate everything that follows this digit. If the third significant digit is #<5#, then you will leave the value of the second significant digit unchanged and eliminate everything that follows this digit.

In your case, you have

#color(red)(color(black)(4.)4color(blue)(4)color(black)(5))#

Here

  • #color(red)(4) -># the second significant digit
  • #color(blue)(4) -># the third significant digit

When you compare the third significant digit to #5#, you see that you have

#color(blue)(4) < 5#

This means that you must leave the second significant digit unchanged and eliminate everything that follows this digit.

#4.4color(red)(cancel(color(black)(45)))#

You will thus have

#4.445 ~~ 4.4 -># rounded to two sig figs

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