Hi There!

As we are not given any data about the other days of July, so DO NOT ASSUME anything that we are not given. In the above chart, we are only given data when the temperature was 90 or more than 90 use only that much.

The total hot days=44
Thus, the percent of hot days in july=15/44=34%

It is very important, that we can infer the assumption from the question. Here, we cannot assume about other days in July.

Ask if further assistance is needed.

Hope this helps

The total number of days with max temperature 90F or more for St Louis are as follows:
May : 1 day
Jun : 8 days
July : 15 days
Aug : 12 days
Sept : 4 days
Oct : 4 days
Total : 44 days
(All these are approximate number of days inferred from the graph)

Here we have to find what percent of max temperature 90F or more days(total 44 days) occurred in July(15 days)
In mathematical terms : 15 = what percent of 44?

15 = x/100 * 44;
15/44 = x/100;
0.34 * 100 = x;
x = 34%

Hence, answer is option D.

Hit Kudos if this reply helped!:)

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