If 18.9 million computers were in use in 1980 and the number is rising by 19% annually, predict the number of computers in use in 2015. round to the nearest whole number of million. subject: exponential growth and decay

8329 millions.

Step-by-step explanation:

The exponential growth equation is modeled as :

, where A is the initial amount, r is rate of increase and x is the time period.

Given: The number of computers used in 1980= 18.9 million

The rate of growth = 19% =0.19

The number of years from 1980 to 2015= 35

Now, the number of computers in use in 2015 is given by :-

Hence, the number of computers in use in 2015= 8329 millions.

Step-by-step explanation:

A mathematics teacher wanted to see the correlation between test scores and homework. The homework grade (x) and test grade (y) are given in the accompanying table. Write the linear regression equation that represents this set of data, rounding all coefficients to the nearest tenth. Using this equation, estimate the homework grade, to the nearest integer, for a student with a test grade of 31.

Homework Grade (x) Test Grade (y)

58 52

75 66

66 68

85 74

52 38

74 65

78 76