Question:medium

The length, breadth and thickness of a rectangular sheet of metal are 4.234 m, 1.005 m, and 2.01 cm respectively. Give the area and volume of the sheet to correct significant figures.

Updated On: Jan 19, 2026
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Solution and Explanation

Multiplication/Division Rule

The result should have the same number of significant figures as the measurement with the least number of significant figures.

Given Dimensions

DimensionValueSignificant Figures
Length (\(l\))\(4.234 \, \text{m}\)4
Breadth (\(b\))\(1.005 \, \text{m}\)4
Thickness (\(t\))\(2.01 \, \text{cm} = 0.02101 \, \text{m}\)3

Limiting Factor: Thickness has 3 significant figures

Area Calculation

Formula: \( \text{Area} = l \times b \)

\[ 4.234 \times 1.005 = 4.25487 \, \text{m}^2 \]

Raw precision: 5 sig figs (4.25487)

Limit by measurements: Both have 4 sig figs → Round to 4 sig figs

Final Area: \( 4.255 \, \text{m}^2 \) (4 significant figures)

Volume Calculation

Formula: \( \text{Volume} = l \times b \times t \)

\[ 4.234 \times 1.005 \times 0.02101 = 0.089402 \, \text{m}^3 \]

Raw precision: 5 sig figs (0.089402)

Limit by measurements: Thickness (3 sig figs) → Round to 3 sig figs

Final Volume: \( 0.0894 \, \text{m}^3 \) (3 significant figures)

Verification Table

CalculationRaw ResultLimiting Sig FigsRounded Result
Area (\(l \times b\))\(4.25487 \, \text{m}^2\)4 (both dimensions)\(4.255 \, \text{m}^2\)
Volume (\(l \times b \times t\))\(0.089402 \, \text{m}^3\)3 (thickness)\(0.0894 \, \text{m}^3\)

Exam Answer Format:
Area = \( 4.255 \, \text{m}^2 \)
Volume = \( 0.0894 \, \text{m}^3 \)

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