4 friends A, B, C, and D appeared in a certain examination. The marks

Question

4 friends A, B, C, and D appeared in a certain examination. The marks obtained by B is 33.3% less than A and 50% less than C. If the marks obtained by D is at least 2.5 times of the marks of B, then what is the maximum percentage by which the combined score of A and C is more than the score of D?

A. 30%
B. 35%
C. 40%
D. 45%
E. 60%

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LevanKhukhunashvili · Answer

Assume:
A =90 then
B=60 (90*1/3)
C=120 (60/0.5)
D= at least 150

A+C-D=90+120-150=60
(Percentage change/Value of D)*100 = (60/150)*100=40%

In MY opinion
Ans: C

Tuanguyen248 · Answer

B = x 
=>
A =1.5x
C =2x
D>= 2.5x

Q: Maximum of E= (A+C)/D 
Emax <=> Dmin which we already got (2.5x)

=> E= 3.5x/2.5x = 1.4 => Answer: C: 40%

Lowkya · Answer

Given:
B = 33.33% less than A = 50% less than C 
D is atleast 2.5 times B.

Let's assume B = 100.
Then A = 150, C = 200 and D is atleast 250.
Maximum value of (A + C) - D = 350 - 250 = 100.
%  = \frac{100}{250} * 100  = 40%

Option C

EgmatQuantExpert · Answer

Solution

Given:  
 • The marks obtained by B is 33.33% less than A
• The marks obtained by B 50% less than C
• The marks obtained by D is at least 2.5 times of the marks of B

To find:  
 • The maximum percentage by which the combined score of A and C is more than the score of D

Approach and Working:  
Let us assume the marks obtained by A, B, C, and D are a, b, c, and d respectively
 • As B got 33.3% less than A, we can write  b = a – 33.3% of a = a – \frac{a}{3} = \frac{2a}{3} 
• As B got 50% less than C, we can write  b = c – 50% of c = c – \frac{c}{2} = \frac{c}{2} 
• Hence,  b = \frac{2a}{3} = \frac{c}{2} 
 o Or,  a = \frac{3b}{2}  and  c = 2b

• Also, D got at least 2.5 times of B, therefore, we can write  d = 2.5b = \frac{5b}{2}

Now, to maximise the percentage score of A and C over D, we need to minimise the score of D

The minimum score of D = 2.5b =  \frac{5b}{2} 
 • Therefore, the maximum percentage by which the combined score of A and C is more than the score of D =  \frac{a + c – d}{d} * 100  =  (\frac{3b}{2} + 2b – \frac{5b}{2})/ \frac{5b}{2} * 100  = 40%

Hence, the correct answer is option C.

Answer: C

blueviper · Answer

Hi

if A = 90

B = (90*1/3) 30 not 60

Iotaa · Answer

We can simply solve it by converting 33.33% to 1/3 and 50% to 1/2. Let's assume value of A is A & evaluate rest values in term of A

ThatDudeKnows · Answer

We can just Plug In.

A = 3
B = 2
C = 4
D = 5
A+C = 7
A+C is 2 better than D. 
Percent change is difference/original. D is original.
2/5 = 40%

ThatDudeKnowsPluggingIn

bumpbot · Answer

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4 friends A, B, C, and D appeared in a certain examination. The marks

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