Suppose that we want to estimate what percentage of all drivers exceed the 50 km/h speed limit on a certain stretch of road. (a) How large a sample will we need to be at least 99% confident that the error of our estimate, the sample percentage, is at most 3.5% ? (b) How large a sample will we need if we know that 20% of the drivers in a preliminary sample exceed the 50 km/h speed limit on that stretch of road.

Suppose that we want to estimate what percentage of all drivers exceed the 50 km/h speed limit on a certain stretch of road. (a) How large a sample will we need to be at least 99% confident that the error of our estimate, the sample percentage, is at most 3.5% ? (b) How large a sample will we need if we know that 20% of the drivers in a preliminary sample exceed the 50 km/h speed limit on that stretch of road.

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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