﻿ Applications 48 A survey showed that a majority of Americans plan on doing their holiday shopping
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### Question

Applications 48, A survey showed that a majority of Americans plan on doing their holiday shopping oniline because they don't want to spend money on gas driving from store t websiteOctober 24, 2012). Suppose we have a group of 10 sho holiday shopping online and 3 prefer to do their holiday shopping in stores to do th sample of 3 of these 10 shoppers is selected for a more in-depth study of how theandon has impacted their shopping behavior a. What is the probability that exactly 2 prefer shopping online? h. What is the probability that the majority (either 2 or 3) prefer sho in stores. A shopping online

### Solution

xxx X xx xxx xxxxxx variable xxxxxxxx the xxxxxx xx xxxxxx

out xx 3, xxx xxxxxxx xxxxxxxx online.

xxx, the xxxxxxxxxxy xx xxxxxx an xxxxxx shopper = x/xx = 0.7.

xxxx, X ~ xxx(x, x.x)

a) xxxxx, required xxxxxxxxxxy = x(X = x) = x.xxx. (xxx). x) Required xxxxxxxxxxy = x(X >= x) = x(X = x) + x(X = x)

= x.xxx. (xxx).