Question

equivalent experience_ma.912.dp.2.4
the table shows the world record times for the mens 50 meter breaststroke since 1995.
the equation ( y = - 0.109x + 244.607 ) models the relationship between x, the year of the record, and y, the world record time.
based on this model, what is the predicted world record time for the mens 50 meter breaststroke in the year 2020?
interpret your prediction in the context of the data.
when will the world record time for the mens 50 meter breaststroke reach 20 seconds?
interpret your prediction in the context of the data.

Explanation:

Step1: Predict the time for 2020

Substitute \(x = 2020\) into the equation \(y=-0.109x + 244.607\).

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Step2: Find when \(y = 20\)

Set \(y = 20\) in the equation \(y=-0.109x + 244.607\) and solve for \(x\).

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Answer:

• Predicted world - record time for 2020: \(24.4\) seconds. This means that according to the linear model, in the year 2020, the men's 50 - meter breaststroke world record time is expected to be approximately \(24.4\) seconds.
• The world - record time will reach \(20\) seconds around the year \(2061\). This implies that if the current trend (represented by the linear model \(y =-0.109x + 244.607\)) continues, the men's 50 - meter breaststroke world record will be \(20\) seconds in about the year \(2061\).