A taxi charges d dollars for the first two miles and c cents per quarter mile for every mile after the first two miles. Which equation describes the cost of a taxi of n miles in dollars?
A. dn - c/8(100)
B. cd + 4n - 8/200
C. d + (4cn - 8c)/100
D. d + 100cn/4
E. 4cd(n - 2) - 100
The OA is C.
Please, can someone assist me with this PS question? I don't have it clear about how can I solve it. Thanks!
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A taxi charges d dollars for the first two miles and c cents
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BTGmoderatorLU
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Vincen
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Hello BTGmoderatorLU.
Let's take a look at your question.
Here is what we know: a taxi charges:
- "d" dollars for the first two miles
- "c" cents per quarter mile for every mile after the first two miles.
- The trip was "n" miles long.
So, the miles after the first two is described by "n-2".
Now, "c" cents per quarter mile means that he charges 4c cents per mile after the first two miles.
Now, if we convert the last expression to dollars we get 4c/100.
So, the total charge for a "n" miles trip is
$$d+\frac{4c(n-2)}{100}=d+\frac{\left(4cn-8c\right)}{100}.$$
Hence, the correct answer is the option C.
I hope it helps. <i class="em em-smiley"></i>
Let's take a look at your question.
Here is what we know: a taxi charges:
- "d" dollars for the first two miles
- "c" cents per quarter mile for every mile after the first two miles.
- The trip was "n" miles long.
So, the miles after the first two is described by "n-2".
Now, "c" cents per quarter mile means that he charges 4c cents per mile after the first two miles.
Now, if we convert the last expression to dollars we get 4c/100.
So, the total charge for a "n" miles trip is
$$d+\frac{4c(n-2)}{100}=d+\frac{\left(4cn-8c\right)}{100}.$$
Hence, the correct answer is the option C.
I hope it helps. <i class="em em-smiley"></i>
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Jeff@TargetTestPrep
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Since 1 mile has 4 quarter-miles, a trip of n miles has 4n quarter-miles, and after the first 2 miles that charges d dollars, there are 4n - 8 additional quarter-miles that charge c cents (or c/100 dollars) each. Thus, the total cost in dollars is:BTGmoderatorLU wrote:A taxi charges d dollars for the first two miles and c cents per quarter mile for every mile after the first two miles. Which equation describes the cost of a taxi of n miles in dollars?
A. dn - c/8(100)
B. cd + 4n - 8/200
C. d + (4cn - 8c)/100
D. d + 100cn/4
E. 4cd(n - 2) - 100
d + (c/100)(4n - 8)
d + (4cn - 8c)/100
Answer: C
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Hi All,
We're told that a taxi charges D DOLLARS for the first 2 MILES and C CENTS per QUARTER-MILE for every mile after the first 2 miles. Which equation describes cost of a taxi ride of N miles in dollars. This question can be solved conceptually (with Algebra) or by TESTing VALUES.
IF....
D = 2 dollars
C = 3 cents
N = 3 miles
A 3-mile trip would cost 2 dollars (for the first 2 miles) + 3(4) = 12 cents for the 4 additional quarter-miles.
Total price (in dollars) = 2.12
Answer A: dn - c/8(100) = (2)(3) - 3/800 = 6 - 3/800 NOT a match
Answer B: cd + 4n-8/200 = (3)(2) + 4(3)/200 = 6 + 12/200 NOT a match
Answer C: d + (4cn-8c)/100 = 2 + (36 - 24)/100 = 2.12 This IS a MATCH
Answer D: d + 100cn/4 = 2 + 900/4 NOT a match
Answer E: 4cd(n-2) - 100 = 24(1) - 100 NOT a match
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
We're told that a taxi charges D DOLLARS for the first 2 MILES and C CENTS per QUARTER-MILE for every mile after the first 2 miles. Which equation describes cost of a taxi ride of N miles in dollars. This question can be solved conceptually (with Algebra) or by TESTing VALUES.
IF....
D = 2 dollars
C = 3 cents
N = 3 miles
A 3-mile trip would cost 2 dollars (for the first 2 miles) + 3(4) = 12 cents for the 4 additional quarter-miles.
Total price (in dollars) = 2.12
Answer A: dn - c/8(100) = (2)(3) - 3/800 = 6 - 3/800 NOT a match
Answer B: cd + 4n-8/200 = (3)(2) + 4(3)/200 = 6 + 12/200 NOT a match
Answer C: d + (4cn-8c)/100 = 2 + (36 - 24)/100 = 2.12 This IS a MATCH
Answer D: d + 100cn/4 = 2 + 900/4 NOT a match
Answer E: 4cd(n-2) - 100 = 24(1) - 100 NOT a match
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
