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4-100.

The table below shows the amount of money Francis had in his bank account each day since he started his new job.

 Days at New Job Money in Account $0$ $27$ $1$ $70$ $2$ $113$ $3$ $156$

1. Write a rule for the amount of money in Francis's account. Let $x$ represent the number of days and $y$ represent the number of dollars in the account.

1. When will Francis have more than $1000$ in his account?

What was Francis' starting point, or $b$?

What is the growth each month, or $m$?

Substitute these values into the equation $y = mx + b$.

Which variable represents the amount of money?
Substitute $1000$ for this variable in your rule.

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