ok so you mean old school multiplicaton
so what you do is 
count how many decimal places the decimal is from the right for top and bottom 
add them
88.6 is 1
5.01 is 2
1+2=3
remember to move 3 places to left later
get rid of decimals
now we have
88.6
x5.01
so what you do it
take th rightmost number in the bottom row and multiply it by the top row, 1 number at a time from right to left, if it is over 10, put it over next number to add
 886
x501 
 886
now wedo te next place which is zero so just pt zeroes
 886
 x501 
 886
000
and last part is 5
 443 
 886
 x501
 886
 000
4430
add them
 443 
 886
 x501
 886
 000
4430 +
443886
now remember the 3 decimal places from before?
now put those back, move the decimal place 3 places to the left
443886.0, mvoe 3 to left
443.886