in scientific notation, you want (a number less than 10 and more than 0) times 10^x
so 48978 made so that it is less than 10 and more than 0 is
4.8978
we count how many times we divided 48978 by 10 to get 4.8978 and we get 4
so 4.8978 times 10^4
or on an online test
4.8978e+04