Measuring Precision with Rulers

What is the general rule for how precisely you should measure with any tool?

• Measure only to the exact marks on the tool.

• Estimate one place beyond the smallest mark on the tool.

• Estimate two places beyond the smallest mark on the tool.

• Always round to the nearest whole number.

When using a ruler that only shows whole centimeter marks (like 0, 1, 2, 3 cm), what is the most precise way to write down your measurement?

• To the nearest whole centimeter.

• To one decimal place (like 3.5 cm).

• To two decimal places (like 3.25 cm).

• To three decimal places (like 3.215 cm).

If a ruler has marks for every whole centimeter (like 1 cm, 2 cm, 3 cm), how precisely can you measure an object?

• To the nearest whole centimeter.

• To the nearest tenth of a centimeter.

• To the nearest hundredth of a centimeter.

• To the nearest thousandth of a centimeter.

If a ruler has marks for every tenth of a centimeter (like 3.1 cm, 3.2 cm, 3.3 cm), how precisely can you measure an object?

• To the nearest tenth of a centimeter.

• To the nearest hundredth of a centimeter.

• To the nearest thousandth of a centimeter.

• To the nearest whole centimeter.