Which solution below contains an error?
3/x+4/6²=3x/x²+4/x²=3x+4/x²
1/x+2+1/x+2=2/x+2=1/x+1
2/x+1+8/x-6=2x-12/(x+1)(x-6)+8x+8 /(x+1)(x-6)=10x-4/(x+1)(x-6)

a) one student is chosen from classroom a, then a student is chosen from classroom b.  

step-by-step explanation:

independent events are ones in which the probability of one event does not affect the probability of the second event.

one student is chosen from classroom a; this does not affect the chances of choosing a student from classroom b.   this makes these independent events.

when one card is chosen from a standard deck and then set aside before a second card is chosen, the probability of the second card being chosen changes.   this makes them dependent events.

when one student is chosen from classroom a and then a second student is chosen from classroom a, the probability of choosing the second student changes.   this makes them dependent events.

when a letter is chosen from the alphabet and then a second letter is chosen, the probability of choosing the second letter changes.   this makes them dependent events.

answer: x=60

answer: 0.26

i used the calculator on google