01
Have a go first
The Question
A number is doubled, then 7 is subtracted, then the result is tripled to give 45. What was the starting number?
02
Then check together
The Answer
Reveal the Answer
11
Work backwards: 45 ÷ 3 = 15, then 15 + 7 = 22, then 22 ÷ 2 = 11. Draw the machine forwards and then reverse each arrow — inverse operations become obvious rather than memorised.
Now watch the solution
Pencil and paper
Practice Sheet + Marked Answers
The four-question practice sheet, the solutions in our teaching voice and a self-marking quiz for this question are part of The Question Desk course — every school day of the term, with progress you can see. Enrolled group students get it included.
Want a Plan Built Around Your Child, Not Just This Week’s Question?
Small groups of around 4–5 (max 8), matched to your child’s year group and pace. Start with the free baseline assessment and we’ll tell you exactly where they are.
