Jack is 4 times as old as Lacy. 3 years ago the sum of their ages was 64. How old are they now?
Mathematics · College · Tue Nov 03 2020
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Given the statement:
Jack is 4 times as old as Lacy. 3 years ago the sum of their ages was 64.
Determine their current age.
Representation:
Let x =Jack's current age
y =Lacy's current age
y = 3x
According to the second sentence, we can infer that,
(3x + 4) + ( x + 4) = 64
Solution:
Combine similar terms and solve for the value of x.
(3x + 4) + ( x + 4) = 64
3x + 4 + x + 4 = 64
4x + 8 = 64
Transpose 8 on the other side of the equation, hence we must take note that in transposing a number, the sign changes.
4x = 64 - 8
4x = 56
Divdide both sides by 4 in order to find the value of x.
x = 14
Jack's age =14
Lacy's age =(14)(3)
Lacy's age = 42
Final answer:
Jack is 14 years old and Lacy is 42 years old.