fewer, the comparative form of few, is used with words denoting people or countable things
ex:- fewer members, fewer books, fewer than ten contestants.
Less is used with mass nouns, denoting things that cannot be counted
ex:- less money, less music.
In addition, less is normally used with numbers ex:- less than 10,000 and with expressions of measurement or time ex-: less than two weeks, less than four miles away.
When drive-ins were at the height of their popularity in the late 50's , some 4000 existed in the United States, but today there are less than one-quarter that many
B. there are fewer than one quarter as many
c. there are fewer than one quarter of that amount
D.the number is less than one quarter of that amount
E. it is less than one quarter of that amount
Here you can count drive-ins. Hence fewer.
A,D and E is out.
Between B and C, C "that amount" is awkward and less precise.
Hence OA B.
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