How Old Are Andy and Cal in This Mathematical Age Puzzle?

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Discussion Overview

The discussion revolves around a mathematical age puzzle involving two friends, Andy and Cal. Participants are attempting to determine their current ages based on a set of complex statements regarding their ages at different times. The scope includes mathematical reasoning and problem-solving related to age-related relationships.

Discussion Character

  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant notes the complexity of the problem and suggests it may not have a solution due to contradictions in verb tenses.
  • Another participant expresses frustration with the time spent on the problem, indicating difficulty in understanding the relationships presented.
  • There is a discussion about the method used to express Cal's age in relation to Andy's past age, with one participant questioning the validity of their approach using compound functions.
  • Some participants reference similar problems from previous discussions, indicating a broader context of age puzzles.

Areas of Agreement / Disagreement

Participants express differing opinions on the clarity and solvability of the problem. While some find it complicated, others question the logic behind the statements, leading to unresolved disagreements about the problem's structure.

Contextual Notes

Participants highlight potential issues with the phrasing of the age relationships, which may affect the interpretation of the problem. There are also references to previous problems that may provide context but do not resolve the current discussion.

Who May Find This Useful

Individuals interested in mathematical puzzles, particularly those involving age-related problems and logical reasoning, may find this discussion relevant.

K Sengupta
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Two friends Andy and Cal form a team together. Andy is as old as Cal will be when Andy is twice as old as Cal was when Andy was half as old as the sum of their current ages. Cal is as old as Andy was when Cal was half as old as he will become in ten years.

Determine the respective current ages of Andy and Cal from the abovementioned statements.
 
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Assuming that 0 and 0 are not acceptable answers :wink:
Oh, didn't read that last sentence.
 
Same age :smile:
ehh nevermind :( umm cal is 8 and Andy is 6?

Work will follow later, its bedtime now.
 
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Borek, this problem does seem more complicated that yours though.
 
Yes, in my problem total is given.
 
umm...does this even have a solution? The sentences contradict one another in regards to the verb tenses.
 
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Andy is 40, Cal 30
Last sentence first. "was"=x, "will be"=y incremental years, respectively.
C=A-X; C-X=1/2(C+10) so X=1/2C-5 therefore C=A-1/2C+5 so 3/2C-A=5 (1)
First sentence.
A=C+Y;A+Y=2(C-X) > different X than above, just an intermediate
A-X=(A+C)/2; X=A/2-C/2. Sub into above
A+Y=2(C-A/2+C/2); Y=3C-2A
A=C+3C-2A;4C=3A;C=(3/4)A (2);
sub (2) into (1)
(9/8)A-A=5>>>>>A=40
From (2) C=30
Check:
Last sentence:
Cal is as old as Andy was > Cal is 30 and Andy was 30 10 yrs ago. 10 yrs ago Cal was 20. Is this half as old as Cal will be in 10 yrs ? Cal now 30+10 divide by 2 = 20 >>check
First sentence:
Half sum of current ages =35. Andy now 40 so this is 5 yrs ago. Cal was 25 then. Andy will be twice as old as this = 50 = 10 yrs from now. Is Andy now as old as Cal will be 10 yrs from now ? Cal is 30 +10 = 40 =Andy's age now>>check

I'd like that hour of my life back thank you
 
Last edited:
regor60 said:
Andy is 40, Cal 30
Last sentence first. "was"=x, "will be"=y incremental years, respectively.
C=A-X; C-X=1/2(C+10) so X=1/2C-5 therefore C=A-1/2C+5 so 3/2C-A=5 (1)

I'd like that hour of my life back thank you

Why did you do C = A - X? When I tried this I used compound functions--C(x) = x and A(x) = x + a--why didnt that method work?
 
  • #10
ƒ(x) said:
Why did you do C = A - X? When I tried this I used compound functions--C(x) = x and A(x) = x + a--why didnt that method work?

C=A-X just reflects the statement that "Cal is as old as Andy was..." meaning Cal's age now, C, is the same as Andy's was, meaning some years, X, before Andy's current age, A.

Further, C-X is just Cal's age X years ago, referenced to his age, C, now

I don't know what a compound function is so can't help there
 
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