Weather Variability Comparison

Pre-Algebra · Axiom Academy

LESSON Same Average, Different Spread Two cities share the exact same average temperature, yet one is calm and the other wild — the range is what tells them apart. 1. The Average Hides the Spread Here is one week of daily highs for each town, plotted on the same temperature line . Both weeks balance at exactly 65°F — the two averages land on the very same spot. Watch what happens when we mark how far each town's days reach out from that center. The range turns that spread into a single number: take the highest value in the data and subtract the lowest . It measures the full width the data covers — the distance from the coldest day to the hottest. A measure of spread, not center Run that on each town's week. Each bar below spans from the town's lowest day to its highest, drawn to the same scale — so the bar's width is the range. Week: 64, 66, 61, 67, 69, 63, 65 → lowest 61°F , highest 69°F Week: 58, 81, 49, 72, 54, 76, 65 → lowest 49°F , highest 81°F Same average, four times the range Both weeks average 65°F, yet Swingville's range (32°F) is four times Steadyton's (8°F). A bigger range means the values are more spread out — they wander farther from the center. 3. Smaller Range, More Predictable Follow a marker through each town's week, bounded by that town's range band. Steadyton's marker barely strays from 65°F; Swingville's lurches from frigid to hot. A smaller range means the data stays close to the center — more consistent, more predictable.

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