In a class of 60 ​students, on​ average, 8 will be​ left-handed. If a class includes 12 ​"lefties", estimate how many students are in the class.

8/60=12/x

solve for x
x= 90 students

Well, if there are 12 "lefties" in the class and 8 on average, then it seems like this class is breaking all kinds of left-handed records! Those lefties sure are taking over. So, if we take the average of 8 lefties per class, and we have 12 lefties in this particular class, we can estimate that the total number of students is somewhere in the magical range between "more than a few" and "less than a million".

To estimate the number of students in the class, we can use the average proportion of left-handed students.

Given that the average proportion of left-handed students is 8 out of 60, we can set up a proportion:

8 left-handed students / 60 total students = 12 left-handed students / x total students

Cross-multiplying, we get:

8x = 60 * 12

Dividing both sides by 8, we find:

x = (60 * 12) / 8

Calculating the expression on the right side gives:

x = 720 / 8

x = 90

Therefore, we can estimate that there are approximately 90 students in the class.

To estimate the number of students in the class, we can use proportions.

First, calculate the proportion of left-handed students in the class:
Proportion of left-handed students = Number of left-handed students / Total number of students

The average proportion of left-handed students in the class is 8/60, which simplifies to 2/15.

Next, set up a proportion with the given information:
(Number of left-handed students) / (Total number of students) = (Proportion of left-handed students)

Let's denote the total number of students as "x". Plugging in the known values into the proportion, we get:
12 / x = 2/15

Now, cross-multiply and solve for "x":
15 * 12 = 2 * x
180 = 2x
x = 180 / 2
x = 90

So, the estimated number of students in the class is 90.

You can also think of it with ratios. There are 8 lefties and 52 righties, on average, in a class of 60. The ratio is 8:52. If you divide that in half, you get the equivalent ratio 4:26. Multiply that by 3 to make the four into a 12, and you get the ratio 12:78. That means there are 12 lefties and 78 righties. Add the two and you get a class size of 90.