Hello Everyone!
Let's tackle this question, one thing at a time, and narrow down our options quickly so we know how to answer questions like this when they pop up on the GMAT! To begin, let's take a quick look at the question and highlight any major differences between the options in orange:
Officials at the United States Mint believe that the Sacagawea dollar coin will be used more as a substitute for four quarters rather than for the dollar bill because its weight, only 8.1 grams, is far less than four quarters, which weigh 5.67 grams each.
(A) more as a substitute for four quarters rather than for the dollar bill because its weight, only 8.1 grams, is far less than
(B) more as a substitute for four quarters than the dollar bill because it weighs only 8.1 grams, far lighter than
(C) as a substitute for four quarters more than for the dollar bill because it weighs only 8.1 grams, far less than
(D) as a substitute for four quarters more than the dollar bill because its weight of only 8.1 grams is far lighter than it is for
(E) as a substitute more for four quarters rather than for the dollar bill because its weight, only 8.1 grams, is far less than it is for
After a quick glance over the options, we have several key differences we can focus on:
1. more as a substitute / as a substitute more (Meaning)
2. than / than for (Parallelism)
3. its weight, only 8.1 grams, / it weighs only 8.1 grams / its weight of only 8.1 grams (Wordiness & Clarity)
4. is far less than / far lighter than / far less than / far lighter than it is for / far less than it is for (Wordiness & Idioms)
Let’s start with #2 on our list, which is an either/or split that deals with parallelism! No matter which route we go with here, we’ll eliminate 2-3 options rather quickly. We need to decide if it’s better to say “than” or “than for” here - and that has to do with how we compare four quarters and dollar bills:
(A) more as a substitute for four quarters rather than for the dollar bill because its weight, only 8.1 grams, is far less than
(B) more as a substitute for four quarters than the dollar bill because it weighs only 8.1 grams, far lighter than
(C) as a substitute for four quarters more than for the dollar bill because it weighs only 8.1 grams, far less than
(D) as a substitute for four quarters more than the dollar bill because its weight of only 8.1 grams is far lighter than it is for
(E) as a substitute more for four quarters rather than for the dollar bill because its weight, only 8.1 grams, is far less than it is for
We can eliminate options B & D because the two items aren’t parallel. Now that we have it narrowed down to 3 options, let’s take a look at the other list items to identify other problems and narrow down our options:
(A) more as a substitute for four quarters rather than for the dollar bill because its weight, only 8.1 grams, is far less than
This is INCORRECT for a couple reasons. First, using “rather than” in a comparison is not idiomatically correct. Second, the comparison at the end isn’t parallel - it’s actually trying to compare the weight of a dollar bill to four quarters, instead of comparing the weight of a dollar to the weight of four quarters!
(C) as a substitute for four quarters more than for the dollar bill because it weighs only 8.1 grams, far less than
This is CORRECT! Using “than” to compare two items is the right way to use this idiom structure, and the wording at the end more clearly compares the weight of the dollar to the weight of four quarters, which is parallel!
(E) as a substitute more for four quarters rather than for the dollar bill because its weight, only 8.1 grams, is far less than it is for
This is INCORRECT for the same reasons as option A. In addition to those reasons, the ending “is far less than it is for” is overly wordy and confusing.
There you have it - option C is our winner! By focusing on an either/or split first, we were able to eliminate options quickly, giving us more time to focus on more complex issues!
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