The ratio of two quantities is 3 to 4. If each of the

Question

The ratio of two quantities is 3 to 4. If each of the quantities is increased by 5, what is the ratio of these two new quantities?

A. 3/4
B. 8/9
C. 18/19
D. 23/24
E. It cannot be determined from the information given.

Bunuel · Accepted Answer

You can solve this question if you look at it conceptually: if the two numbers are 3 and 4 then adding 5 to each number will have a huge impact on the ratio but if the two numbers are 3,000,000 and 4,000,000 then adding 5 to each number will have very little impact on the ratio. So, the new ratio cannot be determined from the information given.

Answer: E.

shadabkhaniet · Answer

let the actual ratio be 3k/4k, increase numerator and denominator by 5 => 3k+5/4k+5
Until the value of k is unknown we can not determine the actual ratio.
OR
let the actual be 3/4. After increasing 5 => 8/9
let the actual be 6/8. After increasing 5 => 11/13

Therefore without actual quantities we cannot determine the actual ratio.
Answer is E.

Hope this helps.

Carcass · Answer

Bunuel do you think that such question could still appear during the exam ?? just to know

Bunuel · Answer

Hard to say...

Are you asking because of option E?

Carcass · Answer

Yes. Basically I know that when you encounter a question where option E is among, then it is never the answer (or at least this is the common place)

the reason is that : iof gmat ask you a question says "is impossible to answer" could be to simple, so a trap answer......for this reason I am asking your opinion about.

cumulonimbus · Answer

This question is marked as 'from Official guide' though.

abhinav11 · Answer

I have a small doubt :

Cant the answer be 2 .

As if we originally take the numbers 3 and 4 which satisfies the ratio of 2 quantities be 3:4 and the ratio of increased quantities be 8/9.

I was trying to solve the question without reading the answer choices ans when I find out I cannot solve it . I try to follow hit and trial and 8/9 is there in the options and answered B.

Can any one clear this please ?

Regards, 
Abhinav

580 to 700 + in one month difficult but not impossible

Bunuel · Answer

But if the numbers are different, say 6 and 8, then the new ratio will also be different. Thus you cannot say for sure that the numbers are 3 and 4. Check here a solution: the-ratio-of-two-quantities-is-3-to-4-if-each-of-the-129569.html#p1064455

PareshGmat · Answer

Say the quantities are 3x & 4x

There ratio would be  \frac{3x}{4x} = \frac{3}{4}

After adding 5 to each, new ratio is

\frac{3x+5}{4x+5}

Answer = E

pacifist85 · Answer

Hey,

I also started in the same way as Paresh, but giving different values to the quantities; I then tried to find the actual quantities, like this:

x/y = 3/4
4x=3y
x=3y/4

Then, the new ratio will be:
(x+5)/(y+5), here I substitued the above value for x:
(3y/4+5) / (y+5)
(3y+20)/(4y+20) since y is in any case y, then we add the same, so the ratio of 3/4 actually corresponds to the quantities.

Then, if we add 5 to each it would be 8/9.

I don't know if this makes any sense at all. But, we know that the 2 quantities cannot be the same. So, why are we using the same values (let's say x) above?

PareshGmat · Answer

Ratios are pure numeric. For example, the ratio of 4 kg mangoes to 8 kg oranges = 1:2 Putting the same variable (as I did) is just for convenience

09173140521 · Answer

if this question asks ( both increased by 5  "percent" ) ......the answer is still E ????? it is confusing !

TheUltimateWinner · Answer

Ratio is NOT the fixed thing-it fluctuates. So, increasing in the ratio can't confirm the fixed value.
Thanks__

EatMyDosa · Answer

This is a great question to test your  conceptual understanding  of  RATIOs

Point to note : RATIOs always, always give you a  relationship between numbers , they N EVER give you the actual numbers .

Therefore, whenever something is added/subtracted/multiplied/divided to Numerator (Nr) and Denominator (Dr) of a given RATIO, you cannot determine the new RATIO unless you know the actual values of Nr and Dr.

Here, the ratio of two quantities is 3:4. What this actually means is that for every 3 units of Quantity-1 (in Nr), there are 4-units of Quantity-2 (in Dr). So, when you add 5, you have to add it to actual values of Quantity-1 and Quantity-2 to find the new ratio.

Since we do not know the actual values of Quantity-1 and Quantity-2, we can't find the new RATIO after adding 5 to both Nr and Dr.

Hope this helps!

MathRevolution · Answer

The ratio of two quantities is 3 to 4.

Suppose quantities are '3' and '4'.

Each of the quantities is increased by 5

=> 3 + 5 = 8 and 4 + 5 = 9

New ratio: 8: 9.

Let's change the quantities now: Suppose quantities are 36 and 48 ( Ratio is still 3:4).

=> 36 + 5 = 41 and 48 + 5 = 53

New ratio: 41: 53.

So, for the given ration 3:4, there is 'n' number of possible combinations. And adding'5' to both will always give a different results.

Answer E.

EgmatQuantExpert · Answer

Solution 
 
  Given  
• The ratio of two quantities is 3 to 4.
• Each of the quantities is increased by 5
  To find  
• The ratio of these two new quantities.

Approach and Working out   
• Let the two numbers be 3x and 4x, respectively.
• After the increase, these numbers become 3x + 5 and 4x + 5, respectively.
• Thus, the ratio of these new numbers = (3x + 5)/(4x + 5)
 o We cannot simplify this ratio further. The ratio will depend on the value of x. 
  For example, if x = 1, this ratio will be 8/9, while if x = 2, this ratio will be 11/13.
 Hence, we cannot determine a sure ratio from the given information.

Correct Answer: Option E

Abhishek009 · Answer

\frac{3x+5}{5x+5}

Case I

Let x = 1

So,  \frac{3x+5}{5x+5}=\frac{8}{10}

Case II

Let x = 2

So,  \frac{3x+5}{5x+5}=\frac{11}{15}

Thus, no specific/unique value is possible, hence Answer must be (E)

bumpbot · Answer

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