Trains depart after every 4 minutes.
Total time train takes to complete a circuit= 24 minutes
Evan sets off at 8:30 am, so he will be back at 8:54 am.
So time of trains coming in opposite direction:
8: 34 am
8:38 am
8:42 am
8:46 am
and 8:50 am
5 trains coming in opposite directions.
Now the trains started at 8:06 am from the stations are:
8:06 am
8:10 am
8:14 am
8:18 am
8:22 am
and 8:26 am.
So there are 6 trains started the circuit at 8:06 am.
Now total number of trains=6+5=11 trains
Answer: 11 trains will pass on complete circuit.
Answer:
Since the balls are drawn with replacement, it means the individual probability remain constant,
I have solved this problem on paper (Figures Attached).
Thanks.
Technically, this counts
82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100,101,102,103,104,105, 106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124, 125,126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142, 143,144,145,146,147,148,149,150,151,152
Equation symbol is the name of what you are asking for