19.4 Appropriate Tools and Units (p.428-431)

Precision

• Being very exact and accurate and able reproduce the same measurement over and over again
• Here would be an example of less to more precise units of measurement: miles, yards, feet, inches, 1/2 inches, 1/4 inches... The smaller the unit of measure used, the more precise the measurement.

Try this ruler game from rsinnovative.com to check your understanding of measuring in customary units (inches)

19.3 Relate Customary and Metric

Here are the estimates you need for relating customary and metric

1 in ≈ 2.5 cm

1 ft ≈ 30 cm

1 mi ≈ 1.6 km

1 m ≈ 39 in

1 kg ≈ 2.2 lb

1 oz ≈ 30 g

1 fl oz ≈ 30 ml

1 L ≈ 1 qt