Math Word Algebra Problem

kangphu

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Can someone help me form an equation for this question:

Yvonne is 12. Xavier is twice as old as Yvonne was when Xavier was as old as Yvonne is now. How old is Xavier?
 
Can someone help me form an equation for this question:

Yvonne is 12. Xavier is twice as old as Yvonne was when Xavier was as old as Yvonne is now. How old is Xavier?

Y=12 now
12 = X = 2Y then
 
Can someone help me form an equation for this question...
To learn how to translate from English into math, try here. To learn how to set up and solve age-related word problems, try here.

Yvonne is 12. Xavier is twice as old as Yvonne was when Xavier was as old as Yvonne is now. How old is Xavier?
Using the methods explained at the links, we get:

now:
Yvonne: 12
Xavier: x

then (being t years ago):
Yvonne: 12 - t
Xavier: x - t

Also:

Xavier is (now) twice as old as Yvonne was (then): x = 2(12 - t)

Also:

when (then) Xavier was as old as Yvonne is (now): x - t = 12

So we have:

x = 2(12 - t)
x - t = 12

Solve the second equation for "x=", and plug this in, in place of "x", into the first equation. Solve for the value of t. Back-solve for the requested information. The above does lead to the correct solution. ;)
 
Can someone help me form an equation for this question:

Yvonne is 12. Xavier is twice as old as Yvonne was when Xavier was as old as Yvonne is now. How old is Xavier?
I like to translate each word to algebra.
Let Y = Yvonne age and recall that 'is' means equal.
Yvonne is 12 becomes Y=12--since Yvonne becomes Y, is becomes = and 12 is 12
Let X = Xavier
Xavier(X) is (=) twice as old as (2times) Yvonne (Y) was when Xavier(X) was as old as (=) Yvonne is now(Y or 12).
X=2Y when X=12
So when X=12 we have Y=6. But that was 6 years ago as Y is now 12. So X now is 12+6=18
Does anyone agree with me?
Jomo
 
I don't :wink:
Code:
    z:12                z:16*
    y: 8*               y:12
.....|.........-4........NOW.......
OK fine, not a big deal. But can you show me where I went wrong? We all just want to learn from this site.
Thanks!
Jomo
 
I don't :wink:
Code:
    z:12                z:16*
    y: 8*               y:12
.....|.........-4........NOW.......
First of all your code isn't really showing up - the image is just the top part of a spread sheet calc I suspect.

Next; I agree. I misread the initial problem. I read "Xavier was twice as old as Yvonne .." instead of "Xavier is twice as old as Yvonne ..." in which case

now:
Yvonne: 12
Xavier: x

then (being t years ago):
Yvonne: 12 - t
Xavier: x - t
"Xavier was as old as Yvonne is now": So x-t = 12
"Xavier was twice as old as Yvonne was": So x-t = 12 = 2 (12-t) or 2t = 12, t=6
x = 12 + t = 18

OR (as I said at first)

Y=12 now
12 = X = 2Y then
or Y = 6 then
so 6 years have passed and x = 12+6 = 18 now

So that x-t = 12 become just an x as stapel pointed out and I was incorrect.
 
Last edited:
Can someone help me form an equation for this question:

Yvonne is 12. Xavier is twice as old as Yvonne was when Xavier was as old as Yvonne is now. How old is Xavier?
I would do this with just one variable. "Yvonne is 12" so "when Xavier was as old as Yvonne is now", Xavier was 12. If Yvonne was, then, y years old, Xavier is now 2y years old so that was 2y- 12 years ago. Yvonne is now y+ 2y- 12= 3y- 12= 12. 3y= 24, y= 24/3= 8 so Xavier is now 2y= 2(8)= 16.

As a check, "Xavier was as old as Yvonne is now", 16- 12= 4 years ago. 4 years ago, Yvonne was 12- 4= 8 years old. Yes, 16 is twice 8.
 
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