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

In summary, Andy and Cal are currently forming a team together. The problem involves determining their respective current ages, with the given information that 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. Additionally, it is stated that Cal is as old as Andy was when Cal was half as old as he will become in ten years. The solution involves using the equation C=A-X, where C represents Cal's current age, A represents Andy's current age, and X represents the number of years since Andy's current age.
  • #1
K Sengupta
113
0
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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  • #2
Assuming that 0 and 0 are not acceptable answers :wink:
Oh, didn't read that last sentence.
 
  • #3
Same age :smile:
ehh nevermind :( umm cal is 8 and Andy is 6?

Work will follow later, its bedtime now.
 
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  • #5
Borek, this problem does seem more complicated that yours though.
 
  • #6
Yes, in my problem total is given.
 
  • #7
umm...does this even have a solution? The sentences contradict one another in regards to the verb tenses.
 
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  • #8
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
 
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  • #9
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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Related to How Old Are Andy and Cal in This Mathematical Age Puzzle?

1. What is the "Two friends and age puzzle"?

The "Two friends and age puzzle" is a logic puzzle that involves two friends, Alice and Bob, who have to figure out each other's ages based on some given information.

2. What is the goal of the puzzle?

The goal of the puzzle is for Alice and Bob to use their deductive reasoning skills to determine each other's ages based on the clues given.

3. What are the given clues in the puzzle?

The given clues in the puzzle are: Alice is older than Bob, their ages are both even numbers, the sum of their ages is 25, and the difference between their ages is 3.

4. How do you solve the puzzle?

To solve the puzzle, you can create a grid with Alice's and Bob's possible ages and use the given clues to eliminate incorrect combinations until you are left with the correct answer.

5. Why is the "Two friends and age puzzle" a popular puzzle?

The "Two friends and age puzzle" is a popular puzzle because it requires critical thinking and problem-solving skills, making it both challenging and entertaining for people of all ages.

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