Answer: w = 100
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Step-by-step explanation:
This value of w is larger than 30, so it makes w > 30 true.
At the same time, this value of w is not smaller than 70, so it makes w < 70 false.
If a value of w makes an inequality true, then we consider it a solution.
Put another way: if w = 100, then w > 30 becomes 100 > 30 which is true while w < 70 becomes 100 < 70 which is false.
You can pick any value you want for the answer as long as it's 70 or larger. We can pick w = 70 because w < 70 becomes 70 < 70 which is false. A number cannot be smaller than itself.
In terms of the graph, you can pick any value that is to the right of 70 or at the location of 70.