The question doesn't provide enough information to get an accurate answer. Please provide more information or provide acceptable assumptions.
If there's 21 spoons and 27 forks than there are 48 utensils, and the ratio of spoon to total stilis is 21/48, and if you reduce that it is 7/16. So your answer is B. 7/16.<span />
#1.
Here what you do is cross multiply.

#2.
Same as #1, just cross multiply.

You get the gist?
6 feet is longer because 6 feet = 72 inchs
and because 70 feet = 5.83333