Terms- 350n, 30n, 350, and (50+10n) (four terms)
coefficients- 350,30,and 10
The ratio is 0.394 cm. / 1 in.
This is a mutually exclusive event because you can't choose both at the same turn you can only pick one or the other. so we add the event chances together,
5/35 + 10/35 = 15/35 or reduced 3/7
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