In 2008 a newspaper sold 120 thousand papers, and had 60 thousands people reading online. Their online readership has been increasing by 8 thousand people each year, while their physical paper sales have decreased by 6 thousand papers a year. In what year does online readership exceed physical sales?

t = 5 years

online readership will exceed physical sales in 5 years

Step-by-step explanation:

The number of physical readership can be represented by the equation;

P(t) = 120 - 6t

The number of Online readership can be represented by the equation;

K(t) = 60 + 8t

For online readership to exceed physical sales

K(t) > P(t)

60 + 8t > 120 - 6t

Collecting the like terms;

8t+6t > 120-60

14t>60

t > 60/14

t > 4.29

To the nearest year greater than 4.29.

t = 5 years

online readership will exceed physical sales in 5 years

Approximately 63 business students must be randomly selected to estimate the mean monthly earnings of business students at one college

Step-by-step explanation:

confidence interval = 95%

Standard deviation  = 569

= 1 - 0.95 = .05

 =  = 1.96

We want 95% confidence that the sample mean is within $140 of the population mean

margin of error ( E ) =140

let n be the sample size

margin of error ( E ) =

      squarring both side

n = 63.45

n =63 approximately