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The math problem about probability in grade three is urgent! ! !
1 and * * *, there are three red balls in four balls, the probability of touching the red ball is 3/4, and the probability of touching one is still 3/4, so the probability of touching the red ball is (3/4)*(3/4)=9/ 16.

2. Similarly, the probability of touching a red ball first is 3/4, and then there are three balls and two red balls. The probability of touching a red ball is 2/3, so the probability of touching two red balls is (3/4)*(2/3)= 1/2.