The minimal completion time for the activities is the shortest possible time for all the activities to be finished. In doing this, we look at the path that would require the greatest amount of time. At the START node, we choose the path that would take the longest which is 7 days leading to ACTIVITY D. Next, we choose the path leading to ACTIVITY B which takes 5 days. Then, we move to ACTIVITY C taking 5 days and finally, reach the END which would take 6 days. So, the minimal completion time is:
7 + 5 + 5 + 6 = 23 days
1.) 11 - 3 4/12
2.) 11 - 3 1/3
3.) 11/1 - 3 1/3
4.) 33/3 - 10/3
5.) 23/3 or 7.7 or 7 2/3 is your answer, depending on how you want it
You can work these in your head if you consider the revenue generated by the least contributor (children's tickets) and the difference in revenue between that and the larger contributor ($2.00 -1.50 = 0.50).
If all were children's tickets, the revenue would be 500*$1.50 = $750.00. The actual revenue exceeded that amount by $862.50 -750.00 = 112.50. This difference in revenue is made up by the sale of $112.50/$0.50 = 225 adult tickets. Then the number of children's tickets is 500 -225 = 275.
225 adult tickets were sold
275 children's tickets were sold.
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If you need an equation, you can write an equation using a variable for the number of adult tickets sold (the largest contributor).
.. (500 -a)*1.50 +a*2.00 = 862.50
.. 0.50a = (862.50 -750.00) . . . . . does this look familiar, yet?
.. a = 112.50/0.50 = 225
If they are similar they are by a ration of 1:2 but you dont know all the angles or all the sides.