A marble is selected at random from a jar containing 10 red marbles, 70 yellow marbles, and 20 green marbles. Find the theoretical probability that it is either red or green

The theoretical probability would be 30% or 3/10.

Step-by-step explanation:

Since there are 100 marbles, the total would be 100. 10 red marbles+ 20 green marbles= 30 red and green marbles, which as a fraction, would be 30/100, which can simplify to 30% or 3/10.

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