Mean, Median, and Mode · Sub-skill drill
Weighted Averages
A weighted average accounts for the fact that some values count more than others. The formula is the sum of (value × weight) divided by the sum of weights. SAT questions present these as test scores with different point values, mixtures of substances at different concentrations, or grade calculations with different category weights. The dominant wrong-answer pattern is the simple unweighted average, which the College Board lists as the trap choice. Identify the weights explicitly before computing.
How this sub-skill is tested on the SAT
A weighted average accounts for the fact that some values count more than others. The formula is the sum of (value × weight) divided by the sum of weights. SAT questions present these as test scores with different point values, mixtures of substances at different concentrations, or grade calculations with different category weights. The dominant wrong-answer pattern is the simple unweighted average, which the College Board lists as the trap choice. Identify the weights explicitly before computing.
This sub-skill sits inside the broader Mean, Median, and Mode topic, which is part of the College Board's Problem Solving & Data Analysis content domain. Problem Solving and Data Analysis is where the SAT pretends to be the real world. Every question in this domain is wrapped in context: a recipe, a survey, a clinical trial, a lab measurement, a marketing report. The math itself is rarely harder than middle-school arithmetic — ratios, proportions, percentages, unit conversions, means, medians, scatter plots, two-way tables, and basic probability. What trips students up is the reading. The College Board has spent two decades calibrating these prompts to reward students who slow down on the setup and punish students who rush to compute. ScoreRe
Practice questions in this drill set
Below are 6 practice questions targeting this exact sub-skill, ordered from easier to harder. Each question is tagged with its target score band so you can focus on questions that match the band you are working out of. Worked solutions are open by default — read each one even if you got the question right, because the way the solution is structured often reveals a faster path than the one you used.
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The values 18, 15, 5, 24, 29, 15, 20 were recorded in a science experiment. What is the mean of the data set?
- A 18.00
- B 19
- C 126.00
- D 19.00
Worked solution
Answer: A — 18.00
Sum the values: 18 + 15 + 5 + 24 + 29 + 15 + 20 = 126. Divide by the number of values, 7: 126 / 7 = 18.00.
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The values 30, 20, 18, 1, 10, 27, 23 were recorded in a science experiment. What is the mean of the data set?
- A 18.43
- B 129.00
- C 19.43
- D 20.00
Worked solution
Answer: A — 18.43
Sum the values: 30 + 20 + 18 + 1 + 10 + 27 + 23 = 129. Divide by the number of values, 7: 129 / 7 = 18.43.
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The values 26, 2, 25, 29, 21, 2, 4 were recorded in a science experiment. What is the mean of the data set?
- A 21.00
- B 16.57
- C 109.00
- D 15.57
Worked solution
Answer: D — 15.57
Sum the values: 26 + 2 + 25 + 29 + 21 + 2 + 4 = 109. Divide by the number of values, 7: 109 / 7 = 15.57.
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The values 27, 28, 14, 8, 29, 30, 16 were recorded in a science experiment. What is the mean of the data set?
- A 21.71
- B 152.00
- C 22.71
- D 27.00
Worked solution
Answer: A — 21.71
Sum the values: 27 + 28 + 14 + 8 + 29 + 30 + 16 = 152. Divide by the number of values, 7: 152 / 7 = 21.71.
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The values 16, 4, 8, 15, 14, 21, 13 were recorded in a science experiment. What is the mean of the data set?
- A 91.00
- B 13.00
- C 15
- D 14.00
Worked solution
Answer: B — 13.00
Sum the values: 16 + 4 + 8 + 15 + 14 + 21 + 13 = 91. Divide by the number of values, 7: 91 / 7 = 13.00.
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The values 27, 20, 7, 27, 23, 20, 26 were recorded in a science experiment. What is the mean of the data set?
- A 22.43
- B 21.43
- C 150.00
- D 23.00
Worked solution
Answer: B — 21.43
Sum the values: 27 + 20 + 7 + 27 + 23 + 20 + 26 = 150. Divide by the number of values, 7: 150 / 7 = 21.43.
Why this band assignment matters
Every question in this drill is tagged with a target score band — 400–500, 500–600, 600–700, or 700–800 — based on its difficulty and the patterns the College Board uses for questions at each level. If you are aiming to break out of a 580 plateau, the 600–700 questions in this drill are your highest-leverage practice. If you are chasing 750+, the 700–800 questions here are the ones that separate the top 10% of test takers from everyone else.
Use the band tags to filter your work. If you can confidently solve every 400–500 and 500–600 question without notes, move to the 600–700 set. If those land cleanly, the 700–800 set is your final boss. The worked solutions in this drill are written so that even the hardest questions become learnable patterns once you have seen the structure of the solve a few times.