In: Statistics and Probability
1. A consumer survey was conducted to examine patterns in ownership of tablet computers, cellular telephones, and Blu-ray players. The following data were obtained: 313 people had tablet computers, 232 had cell phones, 267 had Blu-ray players, 67 had all three, 62 had none, 96 had cell phones and Blu-ray players, 57 had cell phones but no computers or Blu-ray players, and 108 had computers and Blu-ray players but no cell phones. (Round your answers to one decimal place.)
(a) What percent of the people surveyed owned a cell phone?
(b) What percent of the people surveyed owned only a cell phone?
2. In a recent survey of monetary donations made by college graduates, the following information was obtained: 91 graduates had donated to a political campaign, 78 had donated to assist medical research, 131 had donated to help preserve the environment, 23 had donated to all three, 24 had donated to none of the three, 32 had donated to a political campaign and to medical research, 44 had donated to medical research and to preserve the environment, and 56 had donated to a political campaign and to preserve the environment. (Round your answers to one decimal place.)
(a) What percent of the college graduates donated to none of the three listed causes?
(b) What percent of the college graduates donated to exactly one of the three listed causes?
1. Notations: T - Tablet computer
C - Cell phone
B - Blu-ray
N= 57 +79+59+29+67+108+63+62=524
a) % of the people surveyed owned a cell phone = (n(C) / N) x 100 =(232/524) x 100 =44.3%
b) % of people surveyed owned only a cell phone= = 10.9%
2. Notations: P - Political
M - Medical research
E - Environment
N=26+25+54+33+23+9+21+24=215
a) % of college graduates donated to none of the three listed causes= = 11.2%
b)% of college graduates donated to exactly one of the three listed causes = = 10500/215 = 48.8%