SOLUTION: Aunt Alice gave each of her three nieces a number of silver dollars equal to their ages. The youngest felt that this was unfair. They agreed to redistribute the money. The youngest

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Question 164470: Aunt Alice gave each of her three nieces a number of silver dollars equal to their ages. The youngest felt that this was unfair. They agreed to redistribute the money. The youngest would split half of her silver dollars evenly with the other two sisters. The middle would then give each of the others 4 silver dollars. Finally, the oldest was to split half of her dollars equally between the two younger sisters. After exchanging the money, each girl had 12 silver dollars. How old are the sisters? (Their ages = 36)
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let a= youngest age
Let b= middle one's age
Let c= oldest one's age
The youngest would split half of her silver dollars evenly with the other two sisters.
The middle and oldest sisters get a%2F4 and a%2F4 silver dollars
The middle, who now has b+%2B+a%2F4 gives 4 to the others
So, the middle now has b+%2B+a%2F4+-+8
The youngest has a%2F2+%2B+4
The oldest has c+%2B+a%2F4+%2B+4
Now the oldest gives 1/2 her money to the other sisters
The oldest now has c%2F2+%2B+a%2F8+%2B+2
Each sister gets %281%2F4%29%2A%28c+%2B+a%2F4+%2B+4%29
So, the middle one has c%2F4+%2B+a%2F16+%2B+1+%2B+b+%2B+a%2F4+-+8
And, the youngest has c%2F4+%2B+a%2F16+%2B+1+%2B+a%2F2+%2B+4
Now each girl has 12 silver dollars
c%2F4+%2B+a%2F16+%2B+1+%2B+a%2F2+%2B+4+=+12
9a%2F16+%2B+c%2F4+%2B+5+=+12 (youngest)
5a%2F16+%2B+b+%2B+c%2F4+-+7+=+12 middle
2a%2F16+%2B+c%2F2+%2B+2+=+12 oldest
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Multiply each equation by 16
(1) 9a+%2B+4c+%2B+80+=+12%2A16
(2) 5a+%2B+16b+%2B+4c+-+112+=+12%2A16
(3) 2a+%2B+8c+%2B+32+=+12%2A16
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Multiply (1) by 2, then subtract (3) from (1)
(1) 18a+%2B+8c+%2B+160+=+2%2A12%2A16
(3) -2a+-+8c+-32+=+-12%2A16
16a+%2B+128+=+12%2A16
16a+=+192+-+128
16a+=+64
a+=+4
Substitute this in (3)
(3) 2%2A4+%2B+8c+%2B+32+=+192
8c+=+192+-+40
8c+=+152
c+=+19
Substitute a and c in (2)
(2) 5%2A4+%2B+16b+%2B+4%2A19+-+112+=+192
20+%2B+16b+%2B+76+-+112+=+192
16b+=+192+%2B+112+-+20+-+76
16b+=+208
b+=+13
Their ages are 4,13 and 19