Answer:
the way that is easiest for me is to do the bunk-bed strategy
for example
154 . x 0.45 . =
5 x 4
5 x 5
5 x 1
then
4 x 4
4 x 5
4 x 1
then u add the #'s together but then cince its a decimal u add the decimal point to the full # , the answer is 6930 but then the decimal 69.3