Tell the world that you just learned a nifty shortcut for dividing by 5 in your head.
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Comment on d percent of d
Do you have to use the p
No, that formula (Part/Whole
No, that formula (Part/Whole = Percent/100) only works when we aren't trying to find some percent OF some value.
Thanks so much!
great!
Great explanation! Now if the
That's correct. If bcd = 4000
That's correct. If bcd = 4000, then we'd get 4000/10,000, which simplifies to 2/5
I worked this out in a
b=10
c=50
d=5.
bcd=(10)(50)(5)=2500
10% of 50 = 5.
5% of 5 = 2.5
This gives me the fraction: 5/2.
Is this incorrect? Thanks!
Almost!
Almost!
Your solution is perfect until you got to "5% of 5 = 2.5"
You're correct to say that 10% of 50 = 5
From this, we can also say that 5% of 50 = 2.5
However, we cannot say that 5% of 5 = 2.5
Instead, let's think of it this way:
10% of 5 = 0.5
So, 5% of 5 = 0.25 = 1/4 (the correct answer)
Cheers,
Brent
Ha! Of course. Thank you for
Hi Brent,
If I leave the answer as 1/4 in the exam, would that be a problem?
A response of 1/4 would be
A response of 1/4 would be perfect.
In fact, any fraction that equals 1/4 (e.g., 2/8, 25/100, 5/20, etc) would be considered correct.
For more on this, start watching the following video at 3:59: https://www.greenlighttestprep.com/module/general-gre-info-and-strategie...
Cheers,
Brent
Simply say b*c*d =2500 and b
=> b/100 * c =d => bc = 100*d--> step 1
=> substitute step 1 in given equation bcd=2500 as 100*d*d=25
=> d power 2 = 25 => d=|5|
=> now d%d means d/100 * d => 5/100*5 = 1/4
Nice work!
Nice work!
what's s percent of r of 200
Does r represent a fraction
Does r represent a fraction (as in "What is s percent of 3/4 of 200?")
Or does r represent a percent (as in "What is s percent of 13 percent of 200?")
I'll answer both questions.
r represents a fraction: What is s percent of r of 200?
s percent of r of 200 = s/100 of (r of 200)
= s/100 of (200r)
= (s/100)(200r)
= 200sr/100
= sr
r represent a percent : What is s percent of r percent of 200?
s percent of r percent of 200 = s/100 of (r/100 of 200)
= s/100 of (r/100)(200)
= s/100 of (200r/100)
= s/100 of (2r)
= (s/100)(2r)
= 2sr/100
= sr/50
Aside: I could have used fewer steps, but played it safe :-)
Hi Brent, could you help with
x* is defined as the 3-digit integer formed by reversing the digits of integer x; for instance, 258* is equal to 852. R is a 3-digit integer such that its units digit is 2 greater than its hundreds digit.
Quantity A
R*-R
Quantity B
200
A Quantity A is greater.
B Quantity B is greater.
C The two quantities are equal.
D The relationship cannot be determined from the information given.
Key concept: The number 538
Key concept: The number 538 has a VALUE of (5 x 100) + (3 x 10) + (8 x 1)
So, for this question we will say that:
a = the hundreds digit of R
b = the tens digit of R
a + 2 = the units digit of R (since the units digit is 2 greater than its hundreds digit)
So the VALUE of R = 100a + 10b + (a + 2) = 101a + 10b + 2
When we reverse the digits to get R* we get:
a + 2 = the hundreds digit of R*
b = the tens digit of R*
a = the units digit of R*
So the VALUE of R* = 100(a + 2) + 10b + a = 100a + 200 + 10b + a = 101a + 10b + 200
Quantity A: R*- R = (101a + 10b + 200) - (101a + 10b + 2) = 198
Quantity B: 200
Answer: B
Brilliant thanks Brent.