Verbal Reasoning - Arithmetic Reasoning - Discussion
Discussion Forum : Arithmetic Reasoning - Section 1 (Q.No. 47)
47.
In a family, each daughter has the same number of brothers as she has sisters and each son has twice as many sisters as he has brothers. How many sons are there in the family ?
Answer: Option
Explanation:
Let d and s represent the number of daughters and sons respectively.
Then, we have :
d - 1 = s and 2 (s - 1) = d.
Solving these two equations, we get: d = 4, s = 3.
Discussion:
5 comments Page 1 of 1.
Vampire A said:
9 years ago
Let the number of daughters be d.
Let the number of sons be s.
Case 1:
Daughter has the same number of brothers as she has sisters.
So,
s = d - 1 (because when the daughter is asked , she doesn't count herself) .
Case 2:
Son has twice as many sisters as he has brothers.
So,
2(s-1) = d (because when the son is asked he doesn't count himself).
Solving both the equations.
d = 4 ; s = 3.
Let the number of sons be s.
Case 1:
Daughter has the same number of brothers as she has sisters.
So,
s = d - 1 (because when the daughter is asked , she doesn't count herself) .
Case 2:
Son has twice as many sisters as he has brothers.
So,
2(s-1) = d (because when the son is asked he doesn't count himself).
Solving both the equations.
d = 4 ; s = 3.
(1)
Prashant said:
10 years ago
Please explain the above calculation in detail so, that I can understand it better.
Dennydanyanuram said:
10 years ago
d is negative means sister.
s is positive means son.
d - 1 = s as per given data ----> I.
2(s - 1) = d as per given data ----> II.
II in I 2s - 2 - 1 = s.
s = 3 submit in equation I.
d - 1 = 3.
d = 4.
s is positive means son.
d - 1 = s as per given data ----> I.
2(s - 1) = d as per given data ----> II.
II in I 2s - 2 - 1 = s.
s = 3 submit in equation I.
d - 1 = 3.
d = 4.
(1)
Parvinder singh said:
1 decade ago
Please tell me how d-1= s and 2 (s-1) = d.
Please explain I can't understand.
Please explain I can't understand.
(1)
Bhavna said:
1 decade ago
Please explain.
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