SLC Sample Quiz

A ruler used to measure a penny has markings every 1 mm. Which measurement for the size of the penny is correctly reported for this ruler?

• 19.05 mm

• 19 mm

• 19.1 mm

A scale used to weigh produce at a market has markings every 0.1 kg. Which measurement for the mass of a dozen apples is correctly reported for this scale?

• 1.87 kg

• 1.9 kg

• 1.875 kg

Answer explanation

The scale measures in increments of 0.1 kg. While 1.875 kg is a precise measurement, it cannot be reported on this scale. The closest valid reading is 1.9 kg, making it the correct choice.

Which numbers are exact (and therefore have an unlimited number of significant figures)?

• 12 inches = 1 foot

• EPA gas mileage rating of 26 miles per gallon

• 1 gross = 144

Answer explanation

Exact numbers, like 12 inches = 1 foot and 1 gross = 144, have an unlimited number of significant figures because they are defined quantities. In contrast, π and EPA ratings are measured values with limited precision.

Perform the calculation to the correct number of significant figures. (8.01 - 7.50)/3.002

• 0.1698867

• 0.17

• 0.170

• 0.1700

Answer explanation

First, calculate 8.01 - 7.50 = 0.51 (2 significant figures). Then, divide by 3.002 (4 significant figures). The result is 0.1698867, but rounded to 2 significant figures gives 0.17, which is the correct answer.

How many significant figures are there in the number 0.080320?

• 3

• 4

• 5

• 6

Answer explanation

The number 0.080320 has 5 significant figures. The leading zeros (0.0) are not counted, but the digits 8, 0, 3, 2, and the trailing zero are significant.

Convert 1285 cm² to m²

• 1.285 x 10⁷ m²

• 12.85 m²

• 0.1285 m²

• 1.285 x 10⁵ m²

Answer explanation

To convert cm² to m², divide by 10,000 (since 1 m² = 10,000 cm²). Thus, 1285 cm² ÷ 10,000 = 0.1285 m². Therefore, the correct answer is 0.1285 m².

Three samples, each of a different substance, are weighed and their volume is measured. The results are tabulated. List the substances in order of decreasing density.

• III > II > I

• I > II > III

• III > I > II

• II > I > III

Answer explanation

To determine density, use the formula density = mass/volume. By comparing the calculated densities, we find that substance III has the highest density, followed by I, and then II, leading to the order III > I > II.

• 34.4 g/cm³

• 0.103 g/cm³

• 121 g/cm³

• 9.75 g/cm³

Answer explanation

To find density, use the formula \( \text{Density} = \frac{\text{Mass}}{\text{Volume}} \). The volume of the sphere is \( V = \frac{4}{3}\pi(3.53)^3 \approx 139.2 \text{ cm}^3 \). Thus, density = \( \frac{1796 \text{ g}}{139.2 \text{ cm}^3} \approx 12.9 \text{ g/cm}^3 \). The closest answer is 9.75 g/cm³.

Convert 85.0 °F to K.

• 181.1 K

• 358 K

• 29.4 K

• 302.6 K

Answer explanation

To convert Fahrenheit to Kelvin, use the formula K = (°F - 32) × 5/9 + 273.15. For 85.0 °F, this results in K = (85 - 32) × 5/9 + 273.15 = 302.6 K, making 302.6 K the correct answer.

A German automobile’s gas mileage is 22 km/L. Convert this quantity to miles per gallon.

• 9.4 mi/gal

• 1.3 x 10² mi/gal

• 52 mi/gal

• 3.6 mi/gal

Answer explanation

To convert 22 km/L to miles per gallon, use the conversion factors: 1 km = 0.621371 miles and 1 L = 0.264172 gallons. Thus, 22 km/L = 22 * 0.621371 / 0.264172 = 52 mi/gal, making 52 mi/gal the correct answer.