Work backwards
Free 4th grade math practice · Common Core MP.1 · no ads, no sign-up
What kids practice: Make sense of problems and keep at them (puzzles that need thinking, not a known method). Questions come at 5 levels and adjust as your child plays: three right in a row move up a level, and two misses in a row make them easier.
Problem Solvers: one of six ways to solve a problem you haven't seen before, the kind of thinking math contests build on. Each question comes with Digit's step-by-step help that walks through the strategy, not just the answer.
⏪ How it works
Start at the end and undo each step, the last one first.
Example: I am thinking of a number. If I add 5 to it and then subtract 3, I get 9. What is my number?
- Undo the last step: 9 + 3 = 12
- Undo adding 5: 12 − 5 = 7
- Check: 7 + 5 − 3 = 9 ✓
Answer: 7
Try a question
I am thinking of a number. If I add 4 to it and then subtract 9, I get 11. What is my number?
Play “Work backwards” in a game
🖨️ Printable worksheet, with an answer key →Where it fits in 4th grade
Part of Challenge puzzles 🚀, in the order schools usually teach 4th grade math.
- ← Before: Find the pattern
- Next: Draw a picture →
For parents and teachers
agarwalmath is free, with no ads and no chat, and kids use a made-up nickname, never their real name. Questions are read out loud for young kids. Make a free profile to save progress on every device and see it by Common Core standard: Parents & teachers. Teachers can assign this lesson to a class: Teachers' Guide.