Mario is 16 years older than his sister Mercedes. Together, their ages total 36 years. How old is Mercedes?
Mercedes is 20 years old.
let x = Mario's age
y = Mercedes' age
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Mario is 16 years older than Mercedes; therefore, add 16 to Mercedes' age to get Mario's age. X = Y+16 is eqn 1.
eqn 2 is X + Y = 36
Solve the two equations simultaneously. 20 is not the right age for Mercedes' age. If 20 is her age, then Mario's age is 20 + 16 = 36 and the sum of the ages is 36 + 20 = 56 but the problem says the total is 36. Thus, 20 can't be right for Mercedes' age.
mercedes is 2 years old
mario is 34 years old
the sum of kim and tony's ages is 42. the difference in their ages is 4 years, how old are tony and kim?
32
25&17
Lisa is 7 years older than her sister Annabelle. Which equation relates Lisa's age (a) to Annabelle's age (b)?
To find the correct age for Mercedes, we can solve the system of equations:
x = y + 16 (eqn 1)
x + y = 36 (eqn 2)
Substitute eqn 1 into eqn 2:
(y + 16) + y = 36
Simplify:
2y + 16 = 36
Subtract 16 from both sides:
2y = 20
Divide by 2:
y = 10
Therefore, Mercedes is 10 years old.