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Comment on The Range of Set A
This seemed very challenging
It's a tricky one. I'd say
It's a tricky one. I'd say 700+
Hi in this question when 2x
When we rephrase the target
When we rephrase the target question, we see that the range = 2x + 2y. At this point, we don't have enough information to determine the value of 2x + 2y
However, statement 1 tells us (indirectly) that 2x + 2y = 40. So, we now have enough information. Although there are infinitely many solutions to the equation 2x + 2y = 40, we aren't required to determine the INDIVIDUAL values of x and y to answer the rephrased target question. We are only required to determine the range (which equals 2x + 2y)
To follow up on my last
To follow up on my last comment....IF the target question were "What is the value of x?" then statement 1 would not be sufficient. However, that is not what the target question asks.
Hi Brent,
I solved this question but my answer was D. Here's why...
For Statement 2, I got 7x + 3y = 72.
This lets me know that X and Y must be even numbers. So even factors of 72 that satisfy the condition 0<X<Y are 2 & 36, 4 & 18 and 6 & 12. (8 & 9 work as well but both numbers are not even and the answer for the equation is above 72) So among these numbers only 4 & 18 satisfy the equation for X & Y.
Doesn't this make Statement 2 sufficient?
Hi Torkuma,
Hi Torkuma,
There are two problems with your analysis of statement 2.
You are correct to conclude that 7x + 3y = 72
However, we cannot then conclude that x and y are both EVEN.
For example, x = 9 and y = 3 is a solution to the equation.
It's also important to point out that the question does NOT state that x and y are INTEGERS.
This means 7x + 3y = 72 can have infinitely many solutions.
For example, x = 7.2 and y = 7.2 is also a solution to the equation.
For these reasons, we cannot conclude that x = 4 and y = 18
Cheers,
Brent
I solved this question but my
For statement 2 : only X=3 y=17 ; satisfy the equation
From statement 2, we get: 7x
From statement 2, we get: 7x + 3y = 72
You're correct to say that x = 3 and y = 17 is a solution to the equation 7x + 3y = 72, but there are infinitely many other solutions.
For example, x = 6 and y = 10 is another solution.
And x = 1 and y = 65/3 is a solution.
And x = 2 and y = 58/3 is a solution.
Etc.
Cheers,
Brent
On Statement 2, if we: 7x+3y
Why can't we divide both sides by 7 --> Divide Both Sides by 3--> then Multiply both sides by 2 to get:
2x+2y=6.857..... and then use this to say statement 2 is sufficient as well.
To me it seems like the same logic we used with Statement 1. What am I missing?
Let's try it out and see what
Let's try it out and see what happens...
Start with: 7x + 3y = 72
Divide both sides by 7 to get: x + 3y/7 = 72/7
Divide both sides by 3 to get: x/3 + y/7 = 24/7
Multiply both sides by 2 to get: 2x/3 + 2y/7 = 48/7
Notice that, if we divide both sides by a certain value, we must divide EVERY term by that value.