Some digits are missing from the calculation. Look at the ones place first: which digit times the one-digit number gives the visible last digit of the result?
Work from right to left and use the reverse calculation too: times and divided belong together, with the result you can check the factors.
Write in the missing digits and check the calculation at the end. Exactly one calculation fits.
Example
For parents
What does this exercise practice?
The child understands written multiplication and division place by place instead of as a recipe: carries, place values and the reverse operation have to be kept in mind together.
Common pitfalls
Often only one digit is tried. Better: the ones place narrows down the options, then the tens place fits with the carry.
How to practice at home
Write down a calculation, cover two digits with small pieces of paper and let someone else guess them.
Related: Written multiplying with two places, Written division, Inverse problems