Question 1143420: Darius is 87 years younger than jack. 11 years ago, jacks age was 4 times Darius’s age. How old is Darius now? X= current age of Darius. the equation should contain 87,11, & 4.
I tried solving it this way (x-11)=4(x-87-11) but it’s not adding up right
Found 4 solutions by ankor@dixie-net.com, josmiceli, ikleyn, MathTherapy:
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! Darius is 87 years younger than jack.
x = j - 87
11 years ago, jacks age was 4 times Darius’s age.
j - 11 = 4(x-11)
j = 4x - 44 + 11
j = 4x - 33
How old is Darius now?
in the first equation, replace j with (4x-33)
x = 4x - 33 - 87
x = 4x - 120
x - 4x = -120
-3x = -120/-3
x = 40 yrs is D's age
X= current age of Darius. the equation should contain 87,11, & 4.
x - 11 = 4(x-11) - 87
Answer by josmiceli(19441)  (Show Source):
Answer by ikleyn(52803)  (Show Source):
You can put this solution on YOUR website! .
Darius is X years old.
Jack is (X+87) years old.
11 years ago, Jack was (X+87-11) = (X+76) years old.
11 years ago, Darius was (X-11) years old.
The equation is
X+76 = 4*(X-11).
Solve it to get the answer : Darius is 40 years old now.
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Additions
(a) Then Jack's age is 40 + 87 = 127 years now.
(b) CHECK: 11 years ago Darius was 40-11 = 29 years old; Jack was 127 - 11 = 116 years old;  = 4,
so the condition is satisfied and the solution is correct.
Is it realistic/likelihood or not - it was not asked in the problem, so I do not touch it . . .
Formally, my solution is correct.
Answer by MathTherapy(10552)  (Show Source):
You can put this solution on YOUR website!
Darius is 87 years younger than jack. 11 years ago, jacks age was 4 times Darius’s age. How old is Darius now? X= current age of Darius. the equation should contain 87,11, & 4.
I tried solving it this way (x-11)=4(x-87-11) but it’s not adding up right
With X being Darius' age, Jack is X + 87
We then get: X + 87 - 11 = 4(X - 11) <====== CONTAINS 87, 11, and 4
X + 76 = 4X - 44
X - 4X = - 44 - 76
- 3X = - 120
X, or 
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