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My dad's age is 3 times my age and 5 years ago he was 4 times my age. How old were we 15 years ago and what is my age now?

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Answer to a math question My dad's age is 3 times my age and 5 years ago he was 4 times my age. How old were we 15 years ago and what is my age now?

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Esmeralda
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1. Definimos \( P \) como la edad actual del papá y \( H \) como la edad actual del hijo.
2. Establecemos \( P = 3H \) y \( P - 5 = 4(H - 5) \).
3. Simplificamos la segunda ecuación para obtener \( P \) en función de \( H \):
P - 5 = 4H - 20
P = 4H - 15
4. Igualamos las dos ecuaciones:
3H = 4H - 15
5. Resolvemos para \( H \):
-H = -15
H = 15
6. Sustituimos \( H \) en la primera ecuación para encontrar \( P \):
P = 3H
P = 3(15)
P = 45
7. Calculamos las edades hace 15 años:
P - 15 = 30
H - 15 = 0

Hace\ 15\ años:\ 30\ y\ 0\ años
Edad\ actual:\ 45\ y\ 15\ años

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