Difference between revisions of "1966 AHSME Problems/Problem 34"
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== Solution == | == Solution == | ||
− | <math>\ | + | The circumference of the wheel is <math>\frac{11}{5280}</math> miles. Let the time for the rotation in seconds be <math>t</math>. So <math>rt=\frac{11}{5280}*3600</math>. We also know reducing the time by <math>\frac{1}{4}</math> of a second makes <math>r</math> increase by <math>5</math>. So <math>(r+5)(t-\frac{1}{4})=\frac{11}{5280}*3600</math>. Solving for <math>r</math> we get <math>r=10</math>. So our answer is <math>(B)</math> <math>10</math>. |
== See also == | == See also == | ||
{{AHSME box|year=1966|num-b=33|num-a=35}} | {{AHSME box|year=1966|num-b=33|num-a=35}} | ||
− | [[Category: | + | [[Category:Introductory Algebra Problems]] |
{{MAA Notice}} | {{MAA Notice}} |
Latest revision as of 18:59, 29 May 2024
Problem
Let be the speed in miles per hour at which a wheel, feet in circumference, travels. If the time for a complete rotation of the wheel is shortened by of a second, the speed is increased by miles per hour. Then is:
Solution
The circumference of the wheel is miles. Let the time for the rotation in seconds be . So . We also know reducing the time by of a second makes increase by . So . Solving for we get . So our answer is .
See also
1966 AHSME (Problems • Answer Key • Resources) | ||
Preceded by Problem 33 |
Followed by Problem 35 | |
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All AHSME Problems and Solutions |
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