I am having a hard time calculating this my question is On April 1, 2011, the company paid an insurance company $4,000 for a two-year fire insurance policy. The entire $4,000 was debited to insurance expense.

How do I calculate?

Your question isn't clear.

Calculate what?

Do you need to calculate the portion of insurance that is a current expense for the year 2011 and the portion that is a prepaid expense or prepaid asset?

4000/2 = 2000. = 1 year expense
2000./12 = monthly expense for 1 year
Jan 2011 - Mar 31, 2011 = 3 month x monthly amount

Above is without knowing what you need to calculate.

Purchased dental equipment on January 1 for $80,000, paying $20,000 in cash and signing a $60,000, 3-year note payable. The equipment depreciates $400 per month. Interest is $500 per month

To calculate the monthly insurance expense for the two-year fire insurance policy, you need to divide the total cost by the number of months in the policy. Here's how:

1. Determine the number of months in the policy. In this case, it is a two-year policy, so there are a total of 24 months (12 months multiplied by 2 years).

2. Divide the total cost of the policy ($4,000) by the number of months (24).
$4,000 / 24 = $166.67

So, the monthly insurance expense for this two-year fire insurance policy is $166.67.