Sherry,

I don’t know if it helps but I directly changed these sentences into equations, including also a ‘y’ for the dad’s age... So I have the same way of reasoning as yoyo except for the second question where I ‘think’ in term of equations instead of a trial/error method...

So here is how I thought (sorry for the repetitions, yoyo,

our way do coincide but it is this habit of converting phrase into equations which might be useful to sherry)...

Mary is 12 years old and her father is 42.

→ Mary 12 now, but I choose ‘x’ to represent her age

Father 42 now, but I choose ‘y’ to represent his age

From the above information, I know that : y-x=30

Question a ) How old was Mary’s father when he was 4 times as old as Mary?

Means that I am looking for y when y=4x

So I go back to the equation: y-x=30

4x-x=30

3x=30

x=10

So y= 30 + x= 40

Question b) In how many years’ time will her father be 3 times as old as Mary?

So here y=3x

Here we go again: y-x=30

3x-x=30

2x=30

x=15

So y=45

As Dad is now 42, that will be in three years.

Question 3) cf yoyo

But I add my voice to sherry’s to ask for details about worksheets in this matter...

Jane