#Z=22#. What does this mean? It means that there are 22 massive, positively charged, fundamental particles in the element's nucleus. Given this, the element is unquestionably titanium. Given that there are 22 positive charges in the nucleus, the neutral element must contain an equal number of fundamental negative electric charges; so 22 electrons, particles of negligible mass that are presumed to orbit the massive nucleus.
Now the mass number of #Ti# is given as 50. This relates to the number of massive, nuclear particles. We have accounted for 22 of these in the element's identification. There are thus 28 neutrons, massive,neutrally charged nuclear particles.
So the element is identified by the symbol #""^50Ti#.
Do you have to remember atomic numbers in a chemistry/physics exam?