Question

the sum of two decimal numbers is 5.3. their difference is 1.7 and there product is 6.3 what are the two numbers?

Answer 1

x = one number
y = other number.
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x+y=5.3
x-y=1.7
Solve for x and y.
You don't need the other information but it can be used if you wish.

Answer 2

x+y = 5.3
x-y = 1.7
add them
2x = 7.0
x = 3.5
then y = 1.8

the info that their product is 6.3 was redundant, but checked out.

Answer 3

1.8 and 3.5. I just used guess and check. I knew that the numbers had to be under 5.3. Also, the number in the tenths place had to add up to 13 or 3, so 1.8 and 3.5.