Look at the picture for question.
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Answer:
in steps
Step-by-step explanation:
a. 0.212121... to fraction has multiple answers, the simplest one is
let A = 0.212121...
100A = 21.2121....
100A - A = 99A = 21
A = 21/99 = 7/33 (0.212121...)
Besides 7/33, 707/3333, 70707/333333 ...
b. x hits : 200 bats = 0.212121..
200 x 0.212121.... = 200 x 7/33 = 42.42 (≈ 42)