Question

Mike had $1,800 in his bank account. Thirtydays later, his account balance was $570.Write an integer to represent the averagechange in his balance each day during thistime.

Answer 1

The average of any variable over a period of days is the total amount of that variable divided by the number of days. We need to know the average of change of his account, so we need to find how much the value on the account changed in 30 days and divide it by 30. We have:

`\begin{gathered} \text{avg}=(570-1800)/(30) \\ \text{avg}=(-1230)/(30)=-41 \end{gathered}`

The account decreased 41 dollars in value a day on that month.