SOLUTION: Carl in has two times as many sisters as brothers and his younger sister has two times as many brothers as sisters. How many children did carls parent's have ?

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Question 979632: Carl in has two times as many sisters as brothers and his younger sister has two times as many brothers as sisters. How many children did carls parent's have ?
Found 2 solutions by josmiceli, ankor@dixie-net.com:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +s+ = the number of sister's carl has
Let +b+ = the number of brother's Carl has
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His younger sister has +b+%2B+1+ brothers
( Carl has to be included )
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His younger sister has +s+-+1+ sisters
( she doesn't include herself )
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Equation for Carl's younger sister:
(1) +b+%2B+1+=+2%2A%28+s+-+1+%29+
Equation for Carl:
(2) +s+=+2b+
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(1) +b+%2B+1+=+2s+-+2+
Substitute (2) into (1)
(1) +b+%2B+1+=+2%2A2b+-+2+
(1) +b+%2B+1+=+4b+-+2+
(1) +3b+=+3+
(1) +b+=+1+
and
(2) +s+=+2b+
(2) +s+=+2%2A1+
(2) +s+=+2+
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The total number of children is:
+b+%2B+1+%2B+s+=+1+%2B+1+%2B+2+
+1+%2B+1+%2B+2+=+4+
4 children
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check:
(1) +b+%2B+1+=+2%2A%28+s+-+1+%29+
(1) +1+%2B+1+=+2%2A%28+2+-+1+%29+
(1) +2+=+2+
OK

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Carl in has two times as many sisters as brothers and his younger sister has two times as many brothers as sisters. How many children did carls parent's have ?
:
There has to be 2 boys and 2 girls, 4 children in the family
Carl has one brother and two sisters
sister has one sister and two brothers