Answer:
1/10 or 0.1
Explanation:
Probability of occurrence of any event = number of favorable event by total /number of occurrence of event.
For Sarah
Given Number of frames = 18
Number of strikes made by her = 5
Therefore by using the above formula to get the probability of striking by Sarah will be 5/18.
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For David
Given Number of frames = 25
Number of strikes made by him = 9
Therefore by using the above formula to get the probability of striking by David will be 9/25.
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Since the event of Sarah and David are mutually independent i.e occurrence of one event does not impact the occurrence of other event.
Probability of occurrence of two mutually independent A and B event with Probability P(A) and Probability P(B) is given by P(A) * P(B).
Therefore probability that they both get a strike on their next frame are mutually independent event with probability 5/18 and 9/25 will be calculated by 5/18 * 9/25 = 1/(2*5) = 1/10.