Question

David started with $118.50 in his checking account. Once each week, he can deposit his paycheck of $75.50 into his checking account with extra earnings from his job. When his checking account reaches at least $1100, he plans to open a savings account. How many full weeks will it be before David can open a savings account?

Answer 1

We will determine the number of weeks as follows:

*First: From the text, we have the following expression:

`1100\le75.50w+118.50`

Here w represents the number of weeks.

*Second: We solve for w:

`\Rightarrow75.50w\ge981.5\Rightarrow w\ge13`

So, it will take David at least 13 weeks.

***Procedure:

`1100\le75.50w+118.50\Rightarrow1100-118.50\le75.50w+118.50-118.50`
`981.50\le75.50w\Rightarrow(981.50)/(75.50)\le(75.50w)/(75.50)`
`\Rightarrow13\le w`