1,503 + 847 + 4,219 = 6,569
If the temperature was 3 degrees Fahrenheit at Midnight, and it dropped 7 degrees during the next hour, then the temperature at 1 A.M. would be -4 degrees Fahrenheit. This is true because 3 - 7 = -4.
So, the answer to this question is that the temperature was -4 degrees Fahrenheit at 1 A.M.
Ok
the sets are
natural numbers (or counting numbers), this is like 1,2,3,4,5 etc
whole numbers, this is including 0, so 0,1,2,3,4,5,6 etc
integers, this includes the previoius set and negatives, so -3,-2,-1,0,1,2,3,4,5 etc
rational numbers, this is the set of numbers that can be written in form a/b where b≠0, so all integers can be written like this, like example -3=-3/1, so -7/9 belongs here
-7/9 goes in the rational set