Question

A survey of 120 college students is conducted and the results displayed below show that 90 students have a smartphone, 45 have a tablet, and 10 have neither. Fill in the empty table cells in the two-way frequency table.

Smartphone No Smartphone Total

Tablet 45

No Tablet 10

Total 90 120


What is the probability (rounded to the nearest whole percent) that a randomly selected college student has a tablet but not a smartphone?

A.) 20%

B.) 5%

C.) 17%

D.) 67%

Answer 1

C) 17%

Explanation:

Table: has tablet | no tablet | total

has phone | 25 65 90

no phone | 20 10 30

total | 45 75 120

No tablet total: 120 - 45 = 75

No phone total: 120 - 90 = 30

No tablet phone: 75 - 10 = 65

No phone tablet: 30 - 10 = 20

Both: 45 - 20 = 90 - 65 = 25

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So out of 120 students, 20 of them will have a tablet but no phone. 20/120 = 1/6 = 0.16666... ≈ 17%