His mother asked him to figure out a mathematical problem.
He began to work on mathematical problems that made sense.
He worked on other mathematical problems but was less successful.
At once he would demand the answer to the mathematical problem.
That evening at home he sat down to it as a mathematical problem.
He had begun by doing mathematical problems in his head.
I'd like to work out some of the mathematical problems involved.
The mathematical problem therefore is solved by a physical model of itself.
Look I've worked out the mathematical problems on the defense.
There was a range of supporting material including story books with mathematical problems.
Wörterbuch für Mathematik