Answer:
5.2
Explanation:
Note the equal sign. This means that these two fractions are proportional. First, find common denominators. Note that what you do to the denominator, you do to the numerator:

Isolate the variable, x. Note the equal sign, what you do to one side, you do to the other. Divide 13 from both sides:
(rounded to the nearest tenth).
5.2 is your answer.
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