Answer: 46 years
Step-by-step explanation:
Let the father's age be x and the son's age be y, then 3 years ago:
Father = x - 3
son = y - 3
Then , from the first statement :
x - 3 = 3 ( y - 3 )
x - 3 = 3y - 9
x = 3y - 9 + 3
x = 3y - 6 .......................................... equation 1
In five years time
father = x + 5
son = y + 5
Then , from the second statement
x + 5 = 2 ( y + 5 )
x + 5 = 2y + 10
x = 2y + 10 - 5
x = 2y + 5 ........................ equation 2
Equating equation 1 and 2 , we have
3y -6 = 2y + 5
add 6 to both sides
3y = 2y + 5 + 6
subtract 2y from both sides
3y - 2y = 11
y = 11
substitute y = 11 into equation 1 to find the value of x
x = 3y - 6
x = 3(11) - 6
x = 33 - 6
x = 27
This means that the father is presently 27 years and the son is presently 11 years.
In four years time
father = 27 + 4 = 31
son = 11 + 4 = 15
sum of their ages in four years time will be
31 + 15 = 46 years
Answer:
46 years
Step-by-step explanation:
Answer:
Step-by-step explanation:
In solving this, we'll make some keen assumptions to solve the question.
We'll represent the father's age with "a"
And represent the sons age as "b"
Lets interpret the question.
3 years ago, (means in the past), we'll subtract.
Therefore:
Father's age = a - 3
Sons age = b - 3
The sentence said, " 3 years ago, father was 3 times the sons age*. Interpreting that becomes:
a - 3 = 3 times (b - 3)
Simplifying that gives :
a - 3 = 3(b - 3)
a - 3 = 3b - 9
a = 3b - 9 + 3
a = 3b - 6 ( FIRST EXPRESSION )
The next line says: In five years time (that's in the future, hence we add) he'll be twice his sons age.
Therefore I become:
Father : a + 5
Son : b + 5
a + 5 = 2(b + 5)
a + 5 = 2b + 10
a = 2b + 5 ( SECOND EXPRESSION)
Equating the first and second equation to solve for "a" - the father's age
3b - 6 = 2b + 5
b = 5 + 6
b = 11 years (Sons age)
Substitute b = 1 in the first expression.
a = 3b - 6
a = 3(11) - 6
a = 33 - 6
a = 27 years (Father's age)
Let resolve, the last sentence:
What will be the sum of their ages in 4 years time. (SINCE IT'S IJ THE FUTURE, WE ADD)
Father's age in four years time: 27 + 4 = 31
Son's age in four years time: 11 + 4 = 15.
The sum of their ages in same four years time becomes:
31 + 15 (years)
46 years
