by BlastRoom
Going from a proportion to the cutoff value: the top ten percent, the qualifying score, the middle half.
#probability_and_statistics

20 questions
One question set, multiple game modes. Tap any game to see it in action. Not sure which to pick?
Answer to place stones and capture territory.

Pick a tile, answer, hit bonuses and steals.

Battleship. Sink every enemy ship to win.
Pass the potato before the fuse runs out.
Buy low, sell high, before the news breaks.
Take the wages, or take the whole vault.
Answer, then shoot for the top corner
Scores on a reasoning test for students are normally distributed with mean 100 points and standard deviation 15 points. What score is at the 90th percentile? Round to the nearest whole point.
Completion times for a 5 km practice run are normally distributed with mean 70 minutes and standard deviation 8 minutes. What time is at the 75th percentile? Round to the nearest tenth.
Lengths of trout in a hatchery are normally distributed with mean 40.0 cm and standard deviation 5.0 cm. What length is at the 20th percentile? Round to the nearest tenth.
Chemistry quiz scores are normally distributed with mean 72 points and standard deviation 10 points. What score is at the 85th percentile? Round to the nearest whole point.
Robot battery lives are normally distributed with mean 12.0 hours and standard deviation 2.0 hours. What battery life is at the 10th percentile? Round to the nearest tenth.
Sunflower heights in a garden are normally distributed with mean 55 cm and standard deviation 7 cm. What height is at the 95th percentile? Round to the nearest whole centimeter.
Bus commute times for students are normally distributed with mean 38 minutes and standard deviation 6 minutes. What time is at the 30th percentile? Round to the nearest tenth.
Reaction times for a lab task are normally distributed with mean 5.0 seconds and standard deviation 0.6 seconds. The fastest 4% receive a badge. What is the largest reaction time that receives a badge? Round to the nearest tenth.
Applicant scores on a screening exam are normally distributed with mean 68 points and standard deviation 9 points. Only the top 15% are interviewed. What is the lowest score that earns an interview? Round to the nearest tenth.
Scholarship scores are normally distributed with mean 75 points and standard deviation 7 points. The top 12% receive awards. What is the lowest award score? Round to the nearest tenth.
Steel pin diameters are normally distributed with mean 12.0 mm and standard deviation 0.4 mm. The smallest 8% are rejected. What is the largest diameter that is rejected? Round to the nearest tenth.
Water-quality index scores for lake sites are normally distributed with mean 82 points and standard deviation 8 points. The top 5% of sites get a prize. What is the lowest winning score? Round to the nearest tenth.
Assembly times for a robot are normally distributed with mean 16.0 minutes and standard deviation 2.5 minutes. The fastest 20% pass a speed check. What is the largest passing time? Round to the nearest tenth.
Audition scores are normally distributed with mean 80 points and standard deviation 9 points. Only the top 2% advance to finals. What is the lowest score that advances? Round to the nearest tenth.
Apple weights in an orchard are normally distributed with mean 150 grams and standard deviation 20 grams. Between which two weights does the middle 60% of apples fall? Round to the nearest gram.
Fish tank water temperatures are normally distributed with mean 24.0 °C and standard deviation 1.5 °C. Between which temperatures does the middle 90% fall? Round to the nearest tenth.
Package masses at a shipping desk are normally distributed with mean 2.00 kg and standard deviation 0.30 kg. Between which masses does the middle half fall? Round to the nearest hundredth of a kilogram.
Daily milk yields for cows on a farm are normally distributed with mean 28.0 liters and standard deviation 4.0 liters. Between which yields does the middle 80% fall? Round to the nearest tenth.
Trail race times are normally distributed with mean 52 minutes and standard deviation 8 minutes. Between which times does the middle 40% of runners fall? Round to the nearest tenth.
Ceramic tile lengths are normally distributed with mean 30.00 cm and standard deviation 0.20 cm. Between which lengths does the middle 98% of tiles fall? Round to the nearest hundredth.
z-Scores
40 questions
Comparing Scores from Different Distributions
20 questions
Reading a Normal Curve: Areas and Percentiles
40 questions
Normal Probabilities with normalcdf
40 questions
normalcdf or invNorm: Which Command, and What Goes In It
20 questions
Is This Distribution Approximately Normal?
20 questions
Two-Way Tables: Marginal and Joint Frequencies
40 questions
Conditional Relative Frequency and Association
20 questions
Average Rate of Change
50 questions
Keep the tile or give it to a rival team.
Answer correctly to move your piece.
Texas Hold'em. Answer to draw better cards.
Pick a chest. Big bonus, or lose it all.
Catapult a rival castle or repair your own.
Climb the mountain, or push a rival off it.