SOLUTION: This problem I am having alot of trouble trying to figure out. Please Help!! Mutt is half as old as Jeff will be when Mutt is twice as old as Jeff was when Mutt was half as ol

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Question 79474: This problem I am having alot of trouble trying to figure out. Please Help!!

Mutt is half as old as Jeff will be when Mutt is twice as old as Jeff was when Mutt was half as old as Jeff is now. In five years, the sum of Mutt’s and Jeff’s ages will be 100. How old are Mutt and Jeff now?

Found 2 solutions by ankor@dixie-net.com, josmiceli:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Mutt is half as old as Jeff will be when Mutt is twice as old as Jeff was when Mutt was half as old as Jeff is now. In five years, the sum of Mutt’s and Jeff’s ages will be 100. How old are Mutt and Jeff now?
:
I think the 1st sentence just means "Mutt is half as old as Jeff"
:
M = .5J
:
The sentence "In five years, the sum of Mutt’s and Jeff’s ages will be 100.":
(M + 5) + (J + 5) = 100
M + J + 10 = 100
M + J = 100 -10
M + J = 90
Substitute .5J for M
.5J + J = 90
1.5J = 90
1.5J = 90/1.5
J = 60 years
Then:
M = 30 years old

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Wow! this problem is either pretty tough or I'm just not reading it right.
Even if I'm off base, you might get something out of my method.
The thing to watch carefully is the words "now" and "when" and phrases
"will be" and "was".
Let M = Mutt's age now
Let J = Jeff's age now
The problem is saying that Mutt's age now is half of Jeff's age at
some future time. I'll call that time J+%2B+a where a is in years
So now I've got M+=+%28J+%2B+a%29+%2F+2
When Jeff is J+%2B+a years old, Mutt will be M+%2B+a years old
The problem says that Mutt's age then will be twice what Jeffs
age was at some time in the past. I can now say M+%2B+a+=+2%28J+-+b%29
where b are the years to be subtracted from M and J.
At this time in the past, -b years, what was Mutts age? The problem says
it was M+-+b+=+J+%2F+2, half as old as Jeff is now.
Going back,
M+=+%28J+%2B+a%29+%2F+2 What's a in this equation? To find it, solve
M+%2B+a+=+2%28J+-+b%29 for a.
a+=+2%28J+-+b%29+-+M
substituting,
M+=+%28J+%2B+2%28J+-+b%29+-+M%29+%2F+2
2M+=+J+%2B+2J+-+2b+-+M
3M+=+3J+-+2b What's b? Use M+-+b+=+J+%2F+2 and solve for b.
b+=+M+-+J%2F2
3M+=+3J+-+2%28M+-+J%2F2%29
3M+=+3J+-+2M+%2B+J
5M+=+4J
M+=+4J%2F5
Now use the last piece of information
J+%2B+M+%2B+5+=+100
J+%2B+4J%2F5+%2B+5+=+100
9J%2F5+=+95
J+=+52.78 Jeff's age now
M+=+4J%2F5
M+=+42.22 Mutt's age now
I plugged the answers back into the equations and they checked,
but I've been wrong before, so use your judgement.