I get a mental block with the following type of problems you come across from time to time.
I'm not bothered about the answer but I would like to know how to form the necessary equations.
I get so far and then my mind goes into meltdown.
If someone could please give me the equations, I'll be able to see where I go wrong:-
5 people's ages a,b,c,d,e
a=a+b+c+d+e/5 -this is easy - 4a =b+c+d+e.
Now comes the awkward bits:-
when B= 3a , a+c = a+b+c+d+e
and d =3d (obviously 'cos if b is 3 times his age the other four must be as well)) and e =(2b +1)
All the 5 ages are <50
What are the five ages?
Originally posted by joe shmoO.k.Maybe I've mis-interpreted the thing.
....Thats what I was thinking. No wonder why his head is exploding
I'll type it in as it appears in the newspaper:-
"Five men of different ages under 50 are celebrating their joint birthdays.
Alan's age is the average of their 5 ages.
When Bob is 3 times Alan's age today, the sum of Alan and Colin's ages will be equal to the sum of their 5 ages today.
Furthermore, Derek will be 3 times his age today and Eric will be one year more than double Bob's age today.
Who is the youngest and how old is he?
Good luck and thanks in advance.
1 edit
Originally posted by vendaSeems like a lot of unknowns in to little equations to me. Maybe your notation was just off a bit.
O.k.Maybe I've mis-interpreted the thing.
I'll type it in as it appears in the newspaper:-
"Five men of different ages under 50 are celebrating their joint birthdays.
Alan's age is the average of their 5 ages.
When Bob is 3 times Alan's age today, the sum of Alan and Colin's ages will be equal to the sum of their 5 ages today.
Furthermore, Derek will be 3 ...[text shortened]... ouble Bob's age today.
Who is the youngest and how old is he?
Good luck and thanks in advance.
Let a,b,c,d,e equal their current ages; let A,B,C,D,E equal their future ages.
a = (a + b + c + d + e) / 5
a = ( b + c + d + e ) / 4 1 equation-4 unknowns
At the time of the next set of equations:
B = 3a
A + C = a + b + c + d + e
D = 3d
E = 2b + 1
That is the system as far as I can see. It doesnt lok like a straight forward substitution to me...but have at it.
Originally posted by vendaa = (a+b+c+d+e)/5
O.k.Maybe I've mis-interpreted the thing.
I'll type it in as it appears in the newspaper:-
"Five men of different ages under 50 are celebrating their joint birthdays.
Alan's age is the average of their 5 ages.
When Bob is 3 times Alan's age today, the sum of Alan and Colin's ages will be equal to the sum of their 5 ages today.
Furthermore, Derek will be 3 ...[text shortened]... ouble Bob's age today.
Who is the youngest and how old is he?
Good luck and thanks in advance.
5a = a+b+c+d+e
4a = b+c+d+e
--------
B = 3a
b+y = 3a
y = 3a-b
--------
A+C = a+b+c+d+e
a+y+c+y = a+b+c+d+e
2y = b+d+e
y = (b+d+e)/2
--------
D = 3d
d+y = 3d
y = 2d
--------
E = 1+2b
e+y = 1+2b
y = 1+2b-e
--------
y = 3a-b
y = (b+d+e)/2
y = 2d
y = 1+2b-e
4a = b+c+d+e
-------
(b+d+e)/2 = 2d
b+d+e = 4d
b+e = 3d
-------
2d = 1+2b-e
2d = 1+(b+e)+b-2e
2d = 1+3d+b-2e
2e = 1+d+b
2e = 1+b+(b+e)/3
6e = 3+3b+b+e
5e = 3+4b
idk
Presume idk means I don't know.
Looks to me like you have to assume a value for 1 unknown and then see if the equations work.
Anyway, thanks to you both.
The answers will be in next weeks Sunday times so I'll plug in the numbers and see if the equations work.
In the meantime I might have another look and see if substitution is in fact possible.
Originally posted by vendaIf d =3d is not a typo, d=0 (a newborn)
I get a mental block with the following type of problems you come across from time to time.
I'm not bothered about the answer but I would like to know how to form the necessary equations.
I get so far and then my mind goes into meltdown.
If someone could please give me the equations, I'll be able to see where I go wrong:-
5 people's ages a,b,c,d,e
a=a+b+ ...[text shortened]... four must be as well)) [b] and e =(2b +1)
All the 5 ages are <50
What are the five ages?[/b]
Originally posted by JS357It's not a typo the relevant text from the puzzle is:-
If d =3d is not a typo, d=0 (a newborn)
When Bob is 3 times Alan's age today, the sum of Alan and Colin's ages will be equal to the sum of their 5 ages today.
Furthermore, Derek will be 3 times his age today.
But it's true that d does not equal 3d.
The two unknowns are different
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1 edit
Originally posted by vendaSurely you need
It's not a typo the relevant text from the puzzle is:-
When Bob is 3 times Alan's age today, the sum of Alan and Colin's ages will be equal to the sum of their 5 ages today.
Furthermore, Derek will be 3 times his age today.
But it's true that d does not equal 3d.
The two unknowns are different
d + x = 3d, where x is the 'in a the future'
So x = 2d, which should reduce the variables. . , the number of years in the future is 2 x D's present age
I think someone else had that earlier?
Originally posted by vendaDerek will be 3 times his age today
O.k.Maybe I've mis-interpreted the thing.
I'll type it in as it appears in the newspaper:-
"Five men of different ages under 50 are celebrating their joint birthdays.
Alan's age is the average of their 5 ages.
When Bob is 3 times Alan's age today, the sum of Alan and Colin's ages will be equal to the sum of their 5 ages today.
Furthermore, Derek will be 3 ...[text shortened]... ouble Bob's age today.
Who is the youngest and how old is he?
Good luck and thanks in advance.
Three times whose age?