Homework Progress 34 / 66 Marks
67%
In a school of 450 students, 110 of them are in the choir,
240 of them are in the band and 60 students are in the choir and the band.
Find the probability that a student chosen at random is in the choir
or the band or both.
You may wish to complete the Venn diagram to help you.
E
Choir
Band
Probability
+

If the rat will chew through the rope in 60 seconds you will be free.
In 7 seconds it will be 14 inches from your chest
In 14 seconds it will be 13 inches from your chest
In 21 seconds it will be 12 inches from your chest
In 28 seconds it will be 11 inches from your chest 
In 35 seconds it will be 10 inches from your chest
In 42 seconds it will be 9 inches
In 49 seconds it will be 8 inches
In 56 seconds it will be 7 inches
In 63 seconds it will be 6 inches  (and you will be free since the rat finished)
In 70 seconds it will be 5 inches
In 77 seconds it will be 4 inches
In 84 seconds it will be 3 inches
In 91 seconds it will be 2 inches
In 98 seconds it will be 1 inch
You have 6 seconds before it swings again and cuts you so you have 104 seconds exactly but lucky for you the rat chewed through the rope 44 seconds ago.