David can read 50 pages in 50 minutes.
(50 pages)/(50 minutes) = 1 page/minute
Since David reads 1 page per minute,
in 80 minutes David can read 80 pages.
I have to go see my dog in the hospital today
Fibonacci is famous for his contributions to number theory.
In his book, Liber abaci he introduce the Hindu-Arabic place-valued decimal systems and the use of Arabic Numerals into Europe.He introduced the bar we use in fractions, previous to this, the numerator has quotations around it. The square root notation is also is Fibonacci method.