Answer:
the first part of the question is missing, so I looked for similar questions to fill in the blanks:
Ben and Marie Gerrard, both in their mid-20s, have been married for 4 years and have two preschool-age children. Ben has an accounting degree and is employed as a cost accountant at an annual salary of $63,000. They're now renting a duplex but wish to buy a home in the suburbs of their rapidly developing city. They've decided they can afford a $210,000 house and hope to find one with the features they desire in a good neighborhood.
If the Gerrards are required to make a minimum 20% down payment, then they need to pay at least $210,000 x 20% = $42,000.
Many lenders require a minimum down payment for a mortgage loan and others charge different interest rates depending on the down payment percentage, e.g. if your down payment represents 30% of the house's value, the interest rate will be lower than a loan with a 20% down payment. The logic behind this is that the higher the down payment, the safer the loan.