I am 3 times as old as Sue is,” Frank said to Ann. On the other hand, I am 15 years older than you John while Sue is 1 year younger than John how old am I

Answer 1

Here's what we know:

f = 3s (Frank is three times as old as Sue)

f = j + 15 (Frank is 15 years older than John)

s = j - 1 (sue is 1 year younger than John)

So we have the puzzle pieces, let's put them together:

3s = j + 15 (Frank is 3 times Sue's age, so that, Sue's age, can be put into f)

3(j - 1) = j + 15 (Sue is one year younger than John, so we can replace that variable now, too)

Now that we have a singular variable, we can solve for John's age. Start by distributing:

3j - 3 = j + 15

Subtract j from both sides:

2j - 3 = 15

Add 3 to both sides:

2j = 18

Divide by 2 to both sides:

j = 9

Now that we know j, we can find the other ages:

f = 9 + 15 = 24

s = 9 - 1 = 8

Check (John is 3 times Sue's age):

24 = 8 * 3

24 = 24

Answer 2

Organize the informations as follows:

F=Frank's age, J=John's age and S = Sue's age.

1. F = 3S (Frank 3 x older than Sue)
2. S = J-1 (Sue 1 year younger than John)
3. F = J+15 (Frank is John's age +15)

Use 2 in 1

F = 3(J-1) = 3J -3

But F = J+15

Therefore, both have to be equal as they refer to Frank's age

J+15 = 3J-3

Rearrange the terms to get J-terms on one side of the equation and the numeric values on the other

18 = 2J, so J = 9

S = J - 1 = 8

F = J+15 = 9+15=24

Also, F = 3(J-1) = 3*8 = 24.

Frank is 24 years old.

Answer 3

F = 3S

F = J + 15

S = J - 1

3S = J + 15

substitute:

3(J-1) = J + 15

3J - 3 = J + 15

2J = 18

J = 9

S = 8

F = 24