10 times
The Problem:
The Process:
Firstly, we must equate length units in meters. Let us convert the race distance unit.
Recall that [tex]\boxed{ \ 1 \ km = 1,000 \ meters \ }[/tex]
Then, [tex]\boxed{ \ 2 \ km = 2 \times 1,000 \ meters \ }[/tex]
Thus, the race distance is 2,000 m.
Secondly, we calculate how many times does he switch strokes during the race.
Adam changes from breaststroke to a butterfly every 200 m. Let us divide the race distance with the distance of every change.
[tex]\boxed{ \ 2,000 \div 200 = 10 \ times \ }[/tex]
Or it could be like this:
[tex]\boxed{ \ 2,000 \ m \times \frac{1 \ times}{200 \ m} = 10 \ times\ }[/tex]
Thus, Adam switched strokes 10 times during the races.
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How many times does he switch strokes during the first half of the race?
[tex]\boxed{ \ \bigg(\frac{1}{2} \times 2,000\bigg) \div 200 = \ ? \ times \ }[/tex]
[tex]\boxed{ \ 1,000 \div 200 = \ 5 \ times \ }[/tex]
Keywords: while swimming, a 2 km race, Adam changes, from breaststroke, to a butterfly, every 200 m, how many, times, he switch, strokes, during, the race, the first half
