Sure, let's write a detailed, step-by-step solution to find Joana's average daily balance.
1. Identify the balances and their respective days:
- Joana had a balance of \[tex]$1,000 for 9 days.
- Joana had a balance of \$[/tex]750 for 10 days.
- Joana had a balance of \[tex]$850 for 4 days.
- Joana had a balance of \$[/tex]900 for 7 days.
2. Calculate the total balance for each balance amount:
- For the \[tex]$1,000 balance: \( 9 \times 1,000 = 9,000 \)
- For the \$[/tex]750 balance: [tex]\( 10 \times 750 = 7,500 \)[/tex]
- For the \[tex]$850 balance: \( 4 \times 850 = 3,400 \)
- For the \$[/tex]900 balance: [tex]\( 7 \times 900 = 6,300 \)[/tex]
3. Add up the total balance accumulated over all the days:
- [tex]\( 9,000 + 7,500 + 3,400 + 6,300 = 26,200 \)[/tex]
4. Calculate the total number of days:
- [tex]\( 9 + 10 + 4 + 7 = 30 \)[/tex]
5. To find the average daily balance, divide the total balance by the total number of days:
- [tex]\( \frac{26,200}{30} \approx 873.33 \)[/tex]
Now, let's put these values into the expression:
[tex]\[ 9(1,000) + 10(750) + 4(850) + 7(900) \][/tex]
[tex]\[ = (30) \][/tex]
Therefore, Joana's average daily balance is approximately \$873.33.
So, the completed expression is:
[tex]\[ 9(1,000) + 10(750) + 4(850) + 7(900) \div (30) = 873.33 \][/tex]
