A says to B
I am twice as old as you were when i was as old as you are"
The sum of their age is 63
Find A and B's age
2007-07-15 15:06:19 · 8 answers · asked by Manas S 1 in Science & Mathematics ➔ Mathematics
27 and 36
2007-07-15 15:12:21 · answer #1 · answered by john j 1 · 2⤊ 1⤋
"A" is talking about some time in the past. Let's make a variable for that, and say this time in the past is "X" years ago.
"I am twice as old as you were [X years ago]..."
A = 2(B–X)
"...I was [X years ago] as old as you are [now]"
A–X = B
"The sum of their ages is 63."
A + B = 63
You now have 3 equations in 3 unknowns. By substitution and a little algebra, you can find the values of A, B and X (though you don't really care about X).
From eq. 2:
X = A–B
Combine that with eq. 1:
A = 2(B–X)
= 2(B–(A–B))
= 2(2B–A)
= 4B–2A
3A = 4B
A = (4/3)B
Now combine with eq. 3:
A + B = 63
(4/3)B + B = 63
(7/3)B = 63
B = 27
And:
A = (4/3)B = 36
So, A's age is 36; and B's age is 27
2007-07-15 22:20:26 · answer #2 · answered by RickB 7 · 1⤊ 0⤋
the difference of the ages = x = A - B
then A = 2*(B - x), since B is x years younger than A.
A = 2B - 2A + 2B, or 3A = 4B, and A = (4/3)*B.
63 - B = 4/3b, or 63 = 7/3B, so B = 27, and A = 36
2007-07-15 22:29:06 · answer #3 · answered by John V 6 · 1⤊ 0⤋
A = 42; B = 21
2007-07-15 22:14:57 · answer #4 · answered by denmark!!! 1 · 0⤊ 2⤋
b=21 a=42
2007-07-15 22:14:01 · answer #5 · answered by Rachel924 1 · 0⤊ 2⤋
a+b=63
a = 2( b - (a-b) )
a = 4/3 b
a=36, b=27
2007-07-15 22:23:01 · answer #6 · answered by amanaceo 1 · 1⤊ 0⤋
x + y = 63
x = 2 * (y - t)
x - t = y
etc.
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2007-07-15 22:12:21 · answer #7 · answered by oregfiu 7 · 0⤊ 1⤋
is there really an answer...........?
2007-07-15 22:15:06 · answer #8 · answered by Anonymous · 0⤊ 2⤋