Evaluate the following expression [13+(14-10)×2]÷7

The answer is for this expression 4.85

PEMDAS
Parenthesis, Exponent, Multiplication/Division, Addition/Subtraction

(13 + (14 - 10)2)/7
add numbers in parenthesis
(13 + (4)2)/7
multiply 4*2 add to 13
(13 + 8)/7
(21)/7
divide by 7
= 3

Consider for a moment building a tree with all possible choices. The first row would contain 8 books (each possible choice for the first book). Then, the second row would contain 7 books for each book in the first row (the choices possible for the second book). Otherwise, it would be 8*7. Following this principal, we continue to multiply down to 1. 8*7*6*5*4*3*2*1. This is also known as 8!, a factorial.
Finally, 8! = 40,320