# There were 110 books in two bookshelves. If we put half of the books from bookshelf B to bookshelf A, then there will be four times more books in bookshelf A, than there is now in bookshelf B. How many books were in the bookshelves in the beginning?

$\frac{1}{2} B + A = 4 \left(\frac{1}{2} B\right)$
$A + B = 110$
$110 - B = \frac{3}{2} B$
$B = 44$
$A = 66$