I appreciate you coming to this post but I desperately need help on starting this
Every student in a class is asked about the number of cars their family owns. The results of the survey are shown in the histogram below, except the column for the number of families with two cars is missing. If the average number of cars per family is 4/3 then how many families owned two cars?
I don't have a picture but
2 families own 0 cars
8 families own 1 car
x families own 2 cars
2 families own 3 cars
What I am confused about is how to calculate the average. Like do I find the total calls which in this case is 14+x and divide by 4 or do I do something like the total number of families which in this case is 12+x divided by 4?
Appreciate you if you can help me. :)
To calculate the average,
first, for each row, multiply the number of families times the number of cars that they own:
2 · 0 = 0
8 · 1 = 8
x · 2 = 2x
2 · 3 = 6
second: add the totals from each row: 0 + 8 + 2x + 6 = 2x + 14
third: find the total number of families: 2 + 8 + x + 2 = x + 12
fourth: find the average by dividing the result of the second step by the result of the third step:
average = (2x + 14) / (x + 12)
fifth: set this average to the known average: (2x + 14) / (x + 12) = 4/3
sixth: solve this equation for x; this willbe your answer.