Question

Henry is building bookshelves to sell at a furniture store. First, he built 10 small bookshelves and 1 large bookshelf, using a total of 412 nails. Later, he built 10 small bookshelves and 8 large bookshelves, using a total of 776 nails. How many nails does Henry use to build the shelves?

Answer 1

Henry uses 36 nails in large bookshelves and 52 nails in small bookshelves.

Explanation:

Let in each large bookshelves Henry uses x nails and in each small bookshelves, Henry uses y nails.

Now, he built 10 small bookshelves and 1 large bookshelf, using a total of 412 nails.

So, 10x + y = 412 ......... (1)

Again, he built 10 small bookshelves and 8 large bookshelves, using a total of 776 nails.

So, 10x + 8y = 776 ........... (2)

Now, subtracting equation (1) from equation (2) we get, 7y = 364

⇒ y = 52

Again, from equation (1) we get, 10x = 412 - 52 = 360

⇒ x = 36

Therefore, Henry uses 36 nails in large bookshelves and 52 nails in small bookshelves. (Answer)