John’s age is 3/5 of his sister’s age. The total age in four years time is 24 years. How old is John now? Show steps and use try check and revise.

Answer 1

Let's start by defining the variables:
- John's age now: J
- Sister's age now: S

From the given information, we know that John's age is 3/5 of his sister's age. Mathematically, this can be represented as:
J = (3/5)S

In four years time, John will be J+4 years old, and his sister will be S+4 years old. The total age at that time is 24 years, so:
(J+4) + (S+4) = 24

Now, we can substitute the value of J from the first equation into the second equation:
(3/5)S + 4 + S + 4 = 24
(8/5)S + 8 = 24
(8/5)S = 16
S = 10

Now that we have found the sister's age, we can find John's age using the first equation:
J = (3/5)*10
J = 6

Therefore, John is currently 6 years old. Let's check this by substituting the values back into the total age equation:
(6+4) + (10+4) = 14 + 14 = 24

The total age in four years time is indeed 24 years, so the solution is correct. John is currently 6 years old.