Answer:total amount of money that he should pay if he has not used his duty free exemption is $98
Step-by-step explanation:I did this before
Let the average of the other nine cities be x, then the population of the nine districts is 9x. The total population of the city is a + 9x. But a = 3x. Hence, the total population is 3x + 9x = 12x.
Therefore, the percent of the city's population living in district a is 3x/12x * 100 = 25%
15% of the students in the school eat hot lunch.
15%=108
108 is 15% of 720
