find two decimals that have a product of 0.2 and a quotient of 0.8

Question

What two decimals multiplied together have an answer of 0.2 and when divided have an answer of 0.8 ?

Answer 1

Let the numbers be a and b, then ab=0.2 and a/b=0.8, so a=0.8b. Therefore, 0.8b^2=0.2 and b^2=0.2/0.8=2/8=1/4 and b=+1/2 or +0.5 and a=+0.8*0.5=+0.4. The two numbers are therefore 0.5 and 0.4 or -0.5 and -0.4. The quotient is 0.4/0.5.