To solve the problem, we need to carefully analyze the scenario and match the appropriate equation.

1. Define variables:

   • Let $x$ represent the amount Bill invested in the money market account.
   • Therefore, $4000 - x$ is the amount Bill invested in the passbook account.

2. Calculate interest for each account:

   • Interest from the money market account: $x \cdot 0.05 \cdot 1$
   • Interest from the passbook account: $(4000 - x) \cdot 0.02 \cdot 1$

3. Total interest:

   • The total interest earned from both accounts is $110. Therefore: $(x \cdot 0.05 \cdot 1) + ((4000 - x) \cdot 0.02 \cdot 1) = 110$

This corresponds to: $(x)(0.05)(1) + (4000 - x)(0.02)(1) = 110$

Answer:

The correct equation is:
$(x)(0.05)(1) + (4000 - x)(0.02)(1) = 110$

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Would you like a detailed walkthrough of solving this equation for $x$?

5 Related Questions:

1. How do you calculate simple interest for different time periods?
2. What are the key differences between simple and compound interest?
3. Can you show how to simplify and solve the selected equation for $x$?
4. What are other real-life applications of interest calculations?
5. How does varying interest rates affect total interest earned?

Tip:

Always double-check units (e.g., percentages, time in years) to ensure consistent calculations in interest problems.