If seven books cost 14 dollars, use a
ratio table to determine the cost of eight books.
In this question, we need to consider
the number of books and the cost. We will assume that each book cost the
same value. We are told in the question that seven
books cost 14 dollars. We are asked to calculate the cost of
eight books. We can do this by finding the unit cost
first. In this case, this is the cost of one
book. The unit cost is equal to the total
cost divided by the number of units.
In this question, we can calculate the
cost per book by dividing 14 by seven. This is equal to two. Therefore, each book cost two
dollars. We have divided the number of books and
the cost by seven. We can now calculate the cost of eight
books by multiplying two dollars by eight. Two multiplied by eight is equal to
16. Therefore, the cost of eight books is
Finding the unit cost first allows us
to solve problems like this using scaling. We can calculate the total cost of any
number of books by multiplying the unit cost by the number of books.