Answer: 0.86
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Step-by-step explanation:
The table says that
- 5 students got an A
- 10 students got a B
- 15 students got a C
That's 5+10+15 = 30 students out of 35 total.
The probability is therefore 30/35 = 0.8571 approximately which rounds to 0.86
There's roughly an 86% chance of picking someone who got an A, B or C.