1.THE COST TO CHARTER A PLANE IS "D" DOLLARS, WHICH IS TO BE SHARED EQUALLY AMONG THE PASSENGER. THE NUMBER OF PASSENGERS, WHICH WAS ORIGINALLY 12, INCREASES TO 18, DECREASING THE COST BY X AMOUNT PER PERSON.
I would like to know how i can solve this problem in less than 2 min.
I am not sure if this is what you meant but here is the method I use:
Say, number of passengers was 12 and is now 18. Say the cost per person has decreased by $25.
Ratio of number of passenger then and now = 12:18 = 2:3
Then, ratio of cost per person then and now = 3:2 (Cost per person is inversely proportional to number of passengers since Cost per person = Total cost/No of passengers)
The difference of 1 on the ratio scale (3:2) corresponds to 25 so cost per person then was 3*25 = 75 and cost per person now is 2*25 = 50
Also, the total cost 'd' = 75*12 or 50*18 = 900
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