Exercise 23 Page 138

Let's recall what a portions web does — it helps organize our work when we write a number in different forms. The arrows tell us that the numbers are equivalent — they have the same value but are written differently.

Here is a portions web for us to complete.

Remember that to write a decimal as a percent, we multiply by

100

and add the percent symbol

% .

Here is how we do it.

We found that

0.875

expressed as a percent is

87.5 % .

Let's include this result in our web!

Moving on, let's choose one of the forms of the number — the decimal, fraction, or a percent — to express it with words. Lets go for the fraction! Notice that we can read $\frac{7}{8}$ as seven-eighths. Let's put all of our results together for a completed portions web.

Moving clockwise, we are going to rewrite $270 %$ as a decimal and a fraction. Let's do it!

First, we want to write this percent as a decimal. To do this, we ignore the percent symbol and move the decimal point two places to the left. Let's go!

We found that

270 %

expressed as a decimal is

2.70,

or simply

2.7 .

Now, the expression in the middle of the web reads as

two

and

seven - tenths .

Let's write this expression using numbers. We do it by replacing each word with a corresponding number or operation.

two 2 + tenths \frac{7 seven}{1 0}

Take note that this is a sum of a whole number and a fraction. In other words, it is a mixed number. This means we can ignore the plus sign and write the expression as

2 \frac{7}{1 0} .

Finally, let's complete the web!

Subchapter links

3.1.1 Grouping Expressions p.133-134

3.1.2 Identifying Terms in Expressions p.138