Concept explainers
The average number of daily phone calls, C, between two cities varies jointly as the product of their populations, P1 and P2, and inversely as the square of the distance, d, between them.
a. Write an equation that expresses this relationship.
b. The distance between San Francisco (population: 777,000) and Los Angeles (population: 3,695,000) is 420 miles. If the average number of daily phone calls between the cities is 326,000, find the value of k to two decimal places and write the equation of variation.
c. Memphis (population: 650,000) is 400 miles from New Orleans (population: 490,000), Find the average number of daily phone calls, to the nearest whole number between these cities.
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Chapter 3 Solutions
Learning Guide For College Algebra
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