SOLUTION: A father who is 42 years old has a son and a daughter. The daughter is three times as old as the son. In 10 years the sum of all their ages will be 100 years. How old are the two s

Question 1069140: A father who is 42 years old has a son and a daughter. The daughter is three times as old as the son. In 10 years the sum of all their ages will be 100 years. How old are the two siblings at present?
Found 3 solutions by Mini-, MathTherapy, ikleyn:
Answer by Mini-(17)   (Show Source): You can put this solution on YOUR website!
The son is 7 years old and the daughter is 28 years old.
Let the son is X years old.
Then the daughter is 3*X years old.
The sum of all three persons ages in 10 years will be:
100 = X+10 + 3*X+10 + 42+10.
100 = 4*X + 10+10+42+10.
100 = 4*X +72.
4*X = 100-72 = 28.
X = 7.
3*X = 28.
Answer by MathTherapy(10552)   (Show Source): You can put this solution on YOUR website!

A father who is 42 years old has a son and a daughter. The daughter is three times as old as the son. In 10 years the sum of all their ages will be 100 years. How old are the two siblings at present?

See: Age_Word_Problems/1069147
Answer by ikleyn(52799)   (Show Source): You can put this solution on YOUR website!
.
X = 7,
3X = 21.

RELATED QUESTIONS
A father who is 42 years old has a son and a daughter. The daughter is three times as old (answered by Cromlix)
A father who is 42 years old has a son and a daughter. The daughter is three times as old (answered by josgarithmetic)
A father who is 42 years old has a son and a daughter. The daughter is three times as old (answered by Mini-,MathTherapy)
A father has a son and a daughter. The father is five times old as the daughter and the... (answered by ankor@dixie-net.com)
A man 42 years old has a son who is 12 years old. In how many years will the father be as (answered by josmiceli)
a man who is 42 years old has a son of 12 years old. in how many years will the father be (answered by T-Maree,MathTherapy)
A man has a daughter and a son. The son is three years older than the daughter. In 17 (answered by Paul)
a mother who is 40 years old has a 10 year old daughter. In how many years will the... (answered by richwmiller,dabanfield)
A MOTHER IS 6 TIMES AS OLD AS HIS SON AND THREE TIMES AS OLD AS HIS DAUGHTER. IF THE... (answered by ankor@dixie-net.com)