If p/3 = r/2 and r = 0.75s, what is the ratio of p to r to s?

Question

(A) 2 : 3 : 4
(B) 8 : 12 : 9
(C) 9 : 6 : 8
(D) 6 : 4 : 3
(E) 12 : 8 : 3

CareerGeek · Answer

p:r = 3:2
 r:s = 3:4

Take LCM of common values of variable r = LCM (2,3) = 6

—> p:r = 3:2 = 9:6
—> r:s = 3:4 = 6:8

Now, we can compare the values.
—> p:r:s = 9:6:8

Option C

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Lampard42 · Answer

r=.75s multiply by 4 to obtain 4r=3s; p/3=r/2 to be multiplied by 6 to get 2p=3r

Multiply 4r=3s and 2p=3r by 3 and 4 respectively to get 8p=12r=9s.

IMO B

CareerGeek · Answer

Eg: If 2a = 3b. a:b will be 3:2 NOT 2:3.
That’s why we can’t take ratio of above as 8:12:9.

Assume 8p=12r=9s=k (k is any constant)

—> p=k/8, r=k/12 and s=k/9
—> p:r:s = k/8:k/12:k/9 = 1/8:1/12/1/9
Multiply with constant 72 to the above ratio
—> p:r:s = 72*8:72*12:72*9 = 9:6:8.

Hope it’s clear.

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Archit3110 · Answer

given
p:r=3:2
and r=3:4
so
p:r:s
3:2:
 :3:4
9:6:8
IMO C

BrushMyQuant · Answer

Given that p/3 = r/2 and r = 0.75s and we need to find the value of p : r : s

To solve this problem we need to express all the variables in terms of one single variable first. We are doing this as when we take the ratio of p : r : s then we can cancel out the common variable

So, lets express all variables in terms of s.

r = 0.75s =  \frac{3}{4} *s

\frac{p}{3}  =  \frac{r}{2} 
=> p =  \frac{3*r}{2}  =  \frac{3r}{2}  =  \frac{3}{2}  * r =  \frac{3}{2}  *  \frac{3}{4} *s =  \frac{9}{8} s

=> p : r : s =  \frac{9}{8} s :  \frac{3}{4} *s : s =  \frac{9}{8}  :  \frac{3}{4}  : 1
=  \frac{9}{8}  :  \frac{3*2}{8}  :  \frac{8}{8} 
= 9 : 6 : 8

So,  Answer will be C 
Hope it helps!

luisdicampo · Answer

Deconstructing the Question  
We are given two relationships among  p, r, s :
 p/3 = r/2  and  r = 0.75s .
We are asked to find the ratio  p : r : s .

Step-by-step  
From:
 p/3 = r/2

Multiply both sides by 6:
 2p = 3r 
 p = (3/2)r

Given:
 r = 0.75s = 3/4 s

Substitute into p:
 p = (3/2)(3/4)s = 9/8 s

So the ratio is:
 p : r : s = 9/8 : 3/4 : 1

Multiply all terms by 8:
 9 : 6 : 8

Answer: 9 : 6 : 8 (C)

If p/3 = r/2 and r = 0.75s, what is the ratio of p to r to s?

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If p/3 = r/2 and r = 0.75s, what is the ratio of p to r to s?

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