What is the product of the greatest common factor of 4 and 10 and the least common multiple of 4 and 10? will mark brainliest

Well first we can make a gcf chart 
4: 1,2,4
10: 1,2,5,10
we then see that the gcf that they have is 2so 2*2= 4
now for the lcm we can also make a chart
4;4,8,12,16,20,24,28
10; 10,20,30 
we see that their lcm is 10.
so 10*10=100
hope this helps
-turtles12345

How am i goonna know explain