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2 years ago

Round off each of the following numbers to two significant figure 0.436 and 9.000

Chemistry

1 answer:

rodikova [14]2 years ago

6 0

Answer:

0.436 ⇒ 0.44

9.000 ⇒ 9.0

Concept:

Significant figures are where each of the digits of a number are used to express it to the required degree of accuracy, starting from the first nonzero digit.

Therefore, in the context of this question, two significant figure means that two digits of numbers are kept, from left to right, starting from the first nonzero digit.

Solve:

<h2>PART I: Rounding 0.436</h2>

0.436 has 3 significant digits in total starting from left to right

Thus, the last digit should be rounded up / down

Since the last digit is 6, it is greater than 5, so it should be rounded up.

Therefore, a rounded 0.436 is $\Large\boxed{0.44}$

<h2>PART II: Rounding 9.000</h2>

9.000 has 4 significant digits in total starting from left to right

Thus, the last two digits should be rounded up / down

Since the last two digits are 0, it is less than 5, so it should be rounded up (or remained).

Therefore, a rounded 9.000 is $\Large\boxed{9.0}$

Hope this helps!! :)

Please let me know if you have any questions

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