4th Grade Math Practice Test — Units 13–14

Covers Unit 13 (Area and perimeter) and Unit 14 (Units of measurement & conversions). Final Course Module!

Open Study Guide: Free review reference with worked examples and check-yourself problems. Note: Achieving 90% mastery of Units 13 & 14 on Khan Academy beforehand is strongly recommended to prepare for test scoring.

Unit 13 — Area and Perimeter

Concept 1

Perimeter vs. Area Formulas

The Core Distinction:

  • Perimeter (Outside Rim): The distance around the outside of the shape. Measured in regular units (feet, meters, cm).
    P = length + width + length + width = 2l + 2w
  • Area (Inside Space): The square space covered inside the shape. Measured in square units (sq ft, sq cm, m²).
    Area = length × width

Worked Example: Rectangle 8 ft by 5 ft

• Perimeter = 8 + 5 + 8 + 5 = 26 feet (fencing).
• Area = 8 × 5 = 40 square feet (carpet).

Understanding:
Concept 2

Finding Missing Side Lengths

When Given the Area: Divide the area by the known side length: width = Area ÷ length.

When Given the Perimeter: First take half the perimeter (length + width), then subtract the known side!

Worked Example: Perimeter is 30 cm, Length is 9 cm

Half the perimeter is 30 ÷ 2 = 15 cm.
Width = 15 − 9 = 6 cm.
Check: 9 + 6 + 9 + 6 = 30 cm!

Understanding:
Concept 3

Complex & Real-World Rectangles

Word Problems: Pay attention to what the question asks for:

  • "Fencing around a garden" → Perimeter
  • "Grass sod or carpet to cover a floor" → Area
Understanding:

Unit 14 — Measurement Conversions

Concept 4

Customary Unit Conversions

Essential Customary Multipliers:

  • Length: 1 foot = 12 inches • 1 yard = 3 feet = 36 inches
  • Weight: 1 pound (lb) = 16 ounces (oz)
  • Volume: 1 gallon = 4 quarts • 1 quart = 2 pints • 1 cup = 8 fluid ounces
  • Time: 1 hour = 60 minutes • 1 minute = 60 seconds

Worked Example: Convert 5 yards to feet

5 × 3 = 15 feet.

Understanding:
Concept 5

Metric Unit Conversions (Powers of 10)

Metric Multipliers:

  • Length: 1 meter (m) = 100 centimeters (cm) • 1 kilometer (km) = 1,000 meters
  • Mass: 1 kilogram (kg) = 1,000 grams (g)
  • Volume: 1 liter (L) = 1,000 milliliters (mL)

Worked Example: Convert 4 kilograms to grams

4 × 1,000 = 4,000 grams.

Understanding:
Concept 6

Elapsed Time and Word Problems

Elapsed Time Rule: When adding time intervals, remember there are 60 minutes in an hour (not 100!).

Worked Example: Movie Duration

A movie started at 4:15 PM and ended at 6:40 PM. How long was the movie?
4:15 to 6:15 is 2 hours. 6:15 to 6:40 is 25 minutes.
Total elapsed time = 2 hours 25 minutes (or 145 minutes).

Understanding: