| 6 |
a. |
Sample
responses are given.
Suppose
the distance around a classmate's thumb is 5 cm. What
do you expect the distance around the wrist to be?
about
10 cm |
| |
b. |
Write
the measurements from part (a) as a ratio in two ways:
|
| |
c. |
Write
the fraction from part (b)as a decimal.
0.5 |
|
|
| It
is often useful to write a ratio as a single decimal number.
For example, the ratio of 3 to 4 is 0.75, or 0.75 to 1. |
 |
| 7 |
Copy
and complete the table as you answer parts (a) and (b). |
|
|
| a. |
Use
the relationships described by Gulliver on page 397 to
write each body ratio as a fraction and as a decimal.
|
| b. |
Wrap
string to find the ratios for your body. Measure the length
of the string in millimeters. Write each ratio as a fraction
and as a decimal to the nearest hundredth. |
|
|
7.
Sample ratios are given.
a.
1/2, 0.5;
1/2, 0.5
b. 96/196, 0.49;
196/384, 0.51
|
|
|
Look
at your table from Question 7.
Sample
responses are given.
| a. |
How do Gulliver's
ratios compare with your ratios? Which form of the ratios
did you use to compare? Explain your choice.
They
are similar; the decimals. They are simpler to compare
than the fractions. |
| b. |
Do you think Gulliver's ratios are reasonable
estimates? Explain.
Yes;
They are similar to the ones I and most of my classmates
got. |
| 9 |
Discussion
Suppose
the distance around a person's thumb is 9 cm. Explain
how you can use ratios to predict the distance around
the person's neck.
I
would use Gulliver's ratios to find that the distance
around the person's wrist is 18 cm, so the distance
around the person's neck is 36 cm.
|
|
|
See Exs. 1-7 on pp. 406-407.