Average a supplied seasonal record

Supplied materials

• All measurements and observations below are supplied classroom examples. They are not data from actual learners or a claim about a particular real site.
• Paper or browser document; an ordinary calculator is optional.
• Rule: Mean of three supplied values equals their sum divided by three. Formula: (a+b+c)/3. Variable key: a = first record (°C), b = second record (°C), c = third record (°C)
• Distinct worked inputs and result: A distinct illustrative record has 10°C, 12°C and 14°C: (10+12+14)/3=12°C.
• Assessment case 1: Supplied case 1: first record (°C)=12; second record (°C)=15; third record (°C)=18, using the explicitly named quantities. Mean of three supplied values equals their sum divided by three. What result follows?
• Assessment case 2: Supplied case 2: first record (°C)=8; second record (°C)=11; third record (°C)=14, using the explicitly named quantities. Mean of three supplied values equals their sum divided by three. What result follows?
• Assessment case 3: Supplied case 3: first record (°C)=20; second record (°C)=22; third record (°C)=24, using the explicitly named quantities. Mean of three supplied values equals their sum divided by three. What result follows?
• Assessment case 4: Supplied case 4: first record (°C)=5; second record (°C)=8; third record (°C)=11, using the explicitly named quantities. Mean of three supplied values equals their sum divided by three. What result follows?
• Assessment case 5: Supplied case 5: first record (°C)=16; second record (°C)=19; third record (°C)=22, using the explicitly named quantities. Mean of three supplied values equals their sum divided by three. What result follows?
• Assessment case 6: Supplied case 6: first record (°C)=9; second record (°C)=12; third record (°C)=15, using the explicitly named quantities. Mean of three supplied values equals their sum divided by three. What result follows?

Learn the idea

A mean summarizes a record but can hide variation. The fictional five-year interval is a sample illustration, not enough by itself to certify a climate normal or a trend.

Mean of three supplied values equals their sum divided by three. The formula in the supplied model is (a+b+c)/3. Variable key: a = first record (°C), b = second record (°C), c = third record (°C). Add every supplied value. Divide by the number of observations.

A distinct illustrative record has 10°C, 12°C and 14°C: (10+12+14)/3=12°C. Means do not show the full spread or establish causation. Track the quantity and unit before calculating. Explain the meaning of a positive, negative or fractional result when relevant. A numerical answer supports the stated model calculation; broader claims require the additional measurements and assumptions described here.

1. Name the measured quantities and their units before substituting values.
2. Write the stated rule and use the variable key to match each symbol to its explicitly named quantity.
3. Calculate each supplied case separately, keeping intermediate arithmetic and the result unit.
4. Explain the result in context and identify the assumption that would invalidate direct use of the rule.

Check your reasoning

Your answer is temporary and is not saved to an account. Download your current answer before leaving or reloading. Written work on paper or in another app stays in your own file.

Take it further

Changed-input task: use the same stated model with first record (°C)=13; second record (°C)=15; third record (°C)=18. Expected result: approximately 15.333333 °C. Explain what changes and keep this assumption: Means do not show the full spread or establish causation.

Nothing here is saved to an account or sent to a teacher. The answer download includes your current choice and any checked feedback. It does not include choices from the separate More practice section. Download that section separately.