Final answer:
The minimum down payment Tom and Tammy need for the house is 20% of the home's purchase price, which calculates to $90,000 for a home listed at $450,000.
Step-by-step explanation:
To calculate the minimum down payment that Tom and Tammy need for a home listed at $450,000 with a down payment requirement of 20%, we use the following formula:
Down Payment = Purchase Price × Percentage
So for a $450,000 home:
Down Payment = $450,000 × 20%
Down Payment = $450,000 × 0.20
Down Payment = $90,000
The minimum amount they need to provide for the down payment is $90,000.