This is an exam question, for Grade 11 high scool students.
How would you go about solving this ?
\(2^{2015}\;*\;5^{2019}\\ =2^{2015}\;*\;5^{2015+4}\\ =2^{2015}\;*\;5^{2015}\;*\;5^{4}\\ =(2*5)^{2015}\;*\;5^{4}\\ =10^{2015}\;*\;625\\ =625\;*\;10^{2015}\\ =6.25*10^2\;*\;10^{2015}\\ =6.25*\;10^{2017}\\\)
That is how I would solve it