Question

Anyone that can solve probability problems please help me.

Answer 1

10.

`P(\text{ice skating}\mid\text{6th grade})=\frac{P(\text{ice skating AND 6th grade})}{P(\text{6th grade})}`

155 of the total 545 students belong to the 6th grade. 46 of the total 545 students belong to the 6th grade and like ice skating. In terms of probability,

`P(\text{6th grade})=(155)/(545)`

`P(\text{ice skating AND 6th grade})=(46)/(545)`

So

`P(\text{ice skating}\mid\text{6th grade})=((46)/(545))/((155)/(545))=(46)/(155)`

11. Similar setup. We know 171 of 545 students like skiing, and there are 74 8th graders that like skiing. So

`P(\text{8th grade}\mid\text{skiing})=((74)/(545))/((171)/(545))=(74)/(171)`