When rounding a number to the nearest 100 , which place value column determines how it rounds?

When rounding a number to the nearest 100 , the digit in the tens place value column determines how the number rounds.

How do you find the first significant figure of a number?

The first significant figure of a number is the first non-zero digit of the number when reading from left to right. For example, the first significant figure of 0.457 is 4.

True or False? The second significant figure of 4.051 is 5.

False. The second significant figure of 4.051 is 0 . The number 0 can be a significant figure as long it is not the first significant figure.

How do you round a number to three significant figures ?

To round a number to three significant figures , find the third significant figure . Check the digit to its right (the fourth significant figure). If this is 0, 1, 2, 3 or 4 then round the 3rd significant figure down . If it is 5, 6, 7, 8 or 9 then round the 3rd significant figure up .

What is the general rule when estimating ?

When estimating , the general rule is to round each number to 1 significant figure .

If you round both numbers up in an addition, will the answer be an overestimate or an underestimate?

If you round both numbers up in an addition, the answer will be an overestimate.

If you round both numbers down in a multiplication, will the answer be an overestimate or an underestimate?

If you round both numbers down in a multiplication, the answer will be an underestimate.

Define the term lower bound .

The lower bound refers to the smallest value that a rounded number could be.

Define the term error interval .

An error interval is a range of values that a rounded number could be.

True or False? When a number is rounded to one decimal place , the answer is 4.8 . The upper bound for this number is 4.85 .

True. When a number is rounded to one decimal place , the answer is 4.8 . The upper bound for this number is 4.85 .

A number has been rounded to the nearest 10 . How do you find the lower and upper bounds for the number?

A number has been rounded to the nearest 10 . Halve 10 to get 5. Add 5 to the rounded number to get the upper bound, and subtract 5 from the rounded number to get the lower bound.

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When rounding a number to the nearest 100, which place value column determines how it rounds?

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Cards in this collection (19)

When rounding a number to the nearest 100, which place value column determines how it rounds?
When rounding a number to the nearest 100, the digit in the tens place value column determines how the number rounds.
How do you find the first significant figure of a number?
The first significant figure of a number is the first non-zero digit of the number when reading from left to right.
For example, the first significant figure of 0.457 is 4.
True or False?
The second significant figure of 4.051 is 5.
False.
The second significant figure of 4.051 is 0.
The number 0 can be a significant figure as long it is not the first significant figure.
How do you round a number to three significant figures?
To round a number to three significant figures, find the third significant figure. Check the digit to its right (the fourth significant figure). If this is 0, 1, 2, 3 or 4 then round the 3rd significant figure down. If it is 5, 6, 7, 8 or 9 then round the 3rd significant figure up.
What is the general rule when estimating?
When estimating, the general rule is to round each number to 1 significant figure.
What calculation should be used to estimate $\frac{812}{4.57}$ ?
To estimate $\frac{812}{4.57}$ use the calculation $\frac{800}{5}$ .
If you round both numbers up in an addition, will the answer be an overestimate or an underestimate?
If you round both numbers up in an addition, the answer will be an overestimate.
If you round both numbers down in a multiplication, will the answer be an overestimate or an underestimate?
If you round both numbers down in a multiplication, the answer will be an underestimate.
Define the term lower bound.
The lower bound refers to the smallest value that a rounded number could be.
Define the term error interval.
An error interval is a range of values that a rounded number could be.
True or False?
If $x$ is a rounded number, the error interval for $x$ can be written as $lower bound \leq x \leq upper bound$ .
False.
If $x$ is a rounded number, the error interval for $x$ can not be written as $lower bound \leq x \leq upper bound$ because $x$ can not be equal to the upper bound.
Instead, $lower bound \leq x < upper bound$ is the correct statement.
True or False?
When a number is rounded to one decimal place, the answer is 4.8. The upper bound for this number is 4.85.
True.
When a number is rounded to one decimal place, the answer is 4.8. The upper bound for this number is 4.85.
A number has been rounded to the nearest 10. How do you find the lower and upper bounds for the number?
A number has been rounded to the nearest 10. Halve 10 to get 5. Add 5 to the rounded number to get the upper bound, and subtract 5 from the rounded number to get the lower bound.
What do you need to do to the lower and upper bounds of $x$ to find the lower and upper bounds of $4 x$ ?
To find the lower and upper bounds of $4 x$ , you need to multiply the lower and upper bounds of $x$ by $4$ .
Which bounds for $a$ and $b$ should you use to find the lower bound of $a + b$ ?
To find the lower bound of $a + b$ , you should use the lower bounds of $a$ and $b$ .
Which bounds for $a$ and $b$ should you use to find the upper bound of $a - b$ ?
To find the upper bound of $a - b$ , you should use the upper bound of $a$ and the lower bound of $b$ .
True or False?
To find the upper bound of $\frac{a}{b}$ , you should use the upper bound of $a$ and the upper bound of $b$ .
False.
To find the upper bound of $\frac{a}{b}$ , you should use the upper bound of $a$ and the lower bound of $b$ .
True or False?
To find the lower bound of $a b$ , you should use the lower bound of $a$ and the lower bound of $b$ .
True.
To find the lower bound of $a b$ , you should use the lower bound of $a$ and the lower bound of $b$ .
The upper bound of $x$ is 3.142345.
The lower bound of $x$ is 3.141871.
What level of accuracy should you use to round $x$ to?
Round $x$ to 4 significant figures (3.142) because both the upper and lower bounds agree as far as 4 significant figures.

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