There are infinitely many possible answers.
40*1
40*1*1
40*1*1*1
and so on.
400*0.1
400*0.1*1
400*0.1*1*1 etc
and then
4000*0.1*0.1
4000*0.1*0.1*1
or
4000*0.01
etc
And then there are irrationals
20*sqrt(2)*sqrt(2)
60
100*40
20 and 20
80
1*40 2*40 4*10 5*8
60
100*40
62
20 and 20
80
1*40 2*40 4*10 5*8
no 3 numbers add to equal 10 and multiply to equal 40.
Here are all the pairs of numbers that equal 120 when multiplied together: 1 x 120 2 x 60 3 x 40 4 x 30 5 x 24 6 x 20 8 x 15 10 x 12 * * * * * These are all the INTEGERS, which is NOT the same as numbers.
1 x 40, 2 x 20, 4 x 10, 5 x 8
62
56
1 x 40, 2 x 20, 4 x 10, 5 x 8