Answer:
Explanation:
This problem is similar to many others in which the sum of two quantities and their difference are given. The solution can be found easily when the equations for the relations are written in standard form.
Setup
Let s and h represent numbers of sodas and hot dogs sold, respectively. The given relations are ...
- s +h = 235 . . . . . combined total
- s -h = 59 . . . . . . difference in the quantities
Solution
Adding the two equations eliminates one variable.
(s +h) +(s -h) = (235) +(59)
2s = 294 . . . . simplify
s = 147 . . . . . .divide by 2
h = 147 -59 = 88 . . . . h is 59 less
147 sodas and 88 hot dogs were sold.
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Additional comment
The solution to a "sum and difference" problem is always the same. One of the numbers is half the sum of those given, and the other is half their difference. ((235-59)/2 = 88)