Hello,
Can you please tell me how to solve this:
What fraction of 3/4 + 1/2 is 3/4 - 1/2?
A) 1/5
B) 1/4
C) 1/3
D) 3/4
E) 5
OA: A
I was trying to solve as follows:
3/4 + 1/2 = 5/4
3/4 - 1/2 = 1/4
So, what fraction of 5/4 is 1/4?
But I was little confused as to how to represent this using algebra.
Thanks,
Sri
To find the fraction
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You were almost there.gmattesttaker2 wrote: What fraction of 3/4 + 1/2 is 3/4 - 1/2?
A) 1/5
B) 1/4
C) 1/3
D) 3/4
E) 5
It may be easier if we rephrase the question.
Notice that these two questions are EQUIVALENT.
"What fraction of X is Y?"
"Y is what fraction of X?"
So, "What fraction of 3/4 + 1/2 is 3/4 - 1/2?" is the same as "3/4 - 1/2 is what fraction of 3/4 + 1/2?"
Here, we go...
"3/4 - 1/2 is what fraction of 3/4 + 1/2?"
In other words: "1/4 is what fraction of 5/4?"
Well, 1/4 is one-fifth the size of 5/4
So, "1/4 is [spoiler]1/5[/spoiler] of 5/4"
Answer: A
Cheers,
Brent
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Since the question stem asks for a FRACTION, we can safely multiply the numerator and the denominator of this fraction by the SAME FACTOR.gmattesttaker2 wrote:Hello,
Can you please tell me how to solve this:
What fraction of 3/4 + 1/2 is 3/4 - 1/2?
A) 1/5
B) 1/4
C) 1/3
D) 3/4
E) 5
OA: A
Simplify the expressions in the question stem by multiplying each expression by 4:
4 * (3/4 + 1/2) = 3+2 = 5.
4 * (3/4 - 1/2) = 3-2 = 1.
Question stem, rephrased:
What fraction of 5 is 1?
In other words:
1 is what fraction of 5?
The correct answer is A.
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Sri, you can just set it up this way:
3/4 - 1/2
---------
3/4 + 1/2
then solve:
1/4
---
5/4
or
1/5
In general, "x is what fraction of y" or "x is what percent of y" is just x/y: the question is essentially asking for the ratio of x to y.
3/4 - 1/2
---------
3/4 + 1/2
then solve:
1/4
---
5/4
or
1/5
In general, "x is what fraction of y" or "x is what percent of y" is just x/y: the question is essentially asking for the ratio of x to y.
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your answer was perfect!
now if you disregard the denominators of 5/4 and 1/4, you will find 1 and 5!
what fraction of 5 is 1? --> 1 is one fifth of 5. so the answer is 1/5.
same applies for 1/4 and 5/4... one quarter is one fifth of 5 quarters
now if you disregard the denominators of 5/4 and 1/4, you will find 1 and 5!
what fraction of 5 is 1? --> 1 is one fifth of 5. so the answer is 1/5.
same applies for 1/4 and 5/4... one quarter is one fifth of 5 quarters
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Well put!Amrabdelnaby wrote:your answer was perfect!
now if you disregard the denominators of 5/4 and 1/4, you will find 1 and 5!
what fraction of 5 is 1? --> 1 is one fifth of 5. so the answer is 1/5.
same applies for 1/4 and 5/4... one quarter is one fifth of 5 quarters
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You were almost there.gmattesttaker2 wrote:Hello,
Can you please tell me how to solve this:
What fraction of 3/4 + 1/2 is 3/4 - 1/2?
A) 1/5
B) 1/4
C) 1/3
D) 3/4
E) 5
OA: A
I was trying to solve as follows:
3/4 + 1/2 = 5/4
3/4 - 1/2 = 1/4
So, what fraction of 5/4 is 1/4?
But I was little confused as to how to represent this using algebra.
Thanks,
Sri
It may be easier if we rephrase the question.
Notice that these two questions are EQUIVALENT.
"What fraction of X is Y?"
"Y is what fraction of X?"
So, "What fraction of 3/4 + 1/2 is 3/4 - 1/2?" is the same as "3/4 - 1/2 is what fraction of 3/4 + 1/2?"
Here, we go...
"3/4 - 1/2 is what fraction of 3/4 + 1/2?"
In other words: "1/4 is what fraction of 5/4?"
Well, 1/4 is one-fifth the size of 5/4
So, "1/4 is 1/5 of 5/4"
Answer: A
Cheers,
Brent
Hi Brent Can u help me understand how u concludedBrent@GMATPrepNow wrote:You were almost there.gmattesttaker2 wrote: What fraction of 3/4 + 1/2 is 3/4 - 1/2?
A) 1/5
B) 1/4
C) 1/3
D) 3/4
E) 5
It may be easier if we rephrase the question.
Notice that these two questions are EQUIVALENT.
"What fraction of X is Y?"
"Y is what fraction of X?"
So, "What fraction of 3/4 + 1/2 is 3/4 - 1/2?" is the same as "3/4 - 1/2 is what fraction of 3/4 + 1/2?"
Here, we go...
"3/4 - 1/2 is what fraction of 3/4 + 1/2?"
In other words: "1/4 is what fraction of 5/4?"
Well, 1/4 is one-fifth the size of 5/4
So, "1/4 is [spoiler]1/5[/spoiler] of 5/4"
Answer: A
Cheers,
Brent
" In other words: "1/4 is what fraction of 5/4?"
Well, 1/4 is one-fifth the size of 5/4
So, "1/4 is 1/5 of 5/4"
Answer: A "
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An easier version of this question is: "What fraction of 6 is 3?" We would write the fraction as 3/6. Similarly, when we are asked "What fraction of 3/4 + 1/2 is 3/4 - 1/2?" we will perform the same operation, as shown here:gmattesttaker2 wrote:Hello,
Can you please tell me how to solve this:
What fraction of 3/4 + 1/2 is 3/4 - 1/2?
A) 1/5
B) 1/4
C) 1/3
D) 3/4
E) 5
(3/4 - 1/2)/(3/4 + 1/2)
Multiplying the expression by 4/4, we have:
(3 - 2)/(3 + 2) = 1/5
Answer: A
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