1. 1/10 1/6
2. (1C10*1C4+1C4*1C3)/2C14=
10/14
3. 1/3 * 4/6 +1/3 * 2/6 +1/3 *3/6=
1/4/(4/6 + 2/6 +3/6)=
4.k^2-k-2≥0 k ≥2
P=3/5
5.P(X+Y)≤1=1/4
P(X+Y)≥1=3/4
1. 1/10 1/6
2. (1C10*1C4+1C4*1C3)/2C14=
10/14
3. 1/3 * 4/6 +1/3 * 2/6 +1/3 *3/6=
1/4/(4/6 + 2/6 +3/6)=
4.k^2-k-2≥0 k ≥2
P=3/5
5.P(X+Y)≤1=1/4
P(X+Y)≥1=3/4