Marie has twice as many brothers as sisters. Her brother Max has the

Question

Marie has twice as many brothers as sisters. Her brother Max has the same number of brothers as sisters. How many brothers and sisters are there?

A. 3
B. 5
C. 6
D. 7
E. 9

KarishmaB · Answer

Max, a boy, has the same number of brothers and sisters. 
So he could have 
Case 1: 1 brother, 1 sister 
Total: 2 boys, 1 girl
OR

Case 2: 2 brothers, 2 sisters 
Total: 3 boys, 2 girls
OR

Case 3: 3 brothers, 3 sisters 
Total: 4 boys, 3 girls
etc.

In any case, the total number of boys will be 1 more than the total number of girls.

Marie has twice as many brothers as sisters. In 
Case 1, she has 2 brothers, 0 sisters - does not satisfy
Case 2, she has 3 brother, 1 sister - does not satisfy
Case 3, she has 4 brothers, 2 sisters - Satisfies. So there are total 4 brothers and 3 sisters i.e. 7

Answer (D)

rahul6019 · Answer

Let total number of sisters - S
Let total number of brothers - B

Mary has twice number of brothers than sisters -> 2(S-1) = B
Max has equal number of brothers and sisters -> B-1 = S

Equating both -> 2(S-1) = S+1 gives S = 3, B = 4

Total number = 7. Correct Answer is D.

v12345 · Answer

For Marie, 2(S-1) = B
For Max, B-1 = S => B = S+1

=> 2(S-1) = S+1 
=> S = 3
And B = 3+1=4
Total = 7

Answer Choice D

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BlueCrab · Answer

Let total no. of sisters are S
And total no. of brothers are B
For Marie: B=2(S-1) (since Marie doesn’t count herself)
For Max: B-1=S (since Max doesn’t count himself)
Solving these eq. will give S=3 and B=4 so total 7

Hope it helps

Aryaa03 · Answer

Sol:

Say Marie has x sisters ==> S = x
and has 2x brothers ===> B = 2x

Total No. of siblings = x + 2x + 1 (1 for Marie)
T = 3x+1

As x has to be an integer, total shall be a multiple of 3 + 1

Only option-D satisfies. (3*2 + 1)

bumpbot · Answer

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Marie has twice as many brothers as sisters. Her brother Max has the

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Marie has twice as many brothers as sisters. Her brother Max has the

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