In the field of mathematics, weight refers to the frequency of each number in the weighted average, also known as weight or weight. First of all, we need to understand the concept of weighted average. The weighted average is the average of different specific gravity data. Weighted average is to calculate the original data in a reasonable proportion. If x 1 appears f 1 times, x2 appears f2 times, …, and xk appears fk times, then (x 1 f1+x2f2+... xkfk)/(f65438) f/kloc- Give three simple examples: 1. There are X people who eat three bowls, Y people who eat two bowls and Z people who eat one bowl in the school canteen. How much does everyone eat on average? (3*x+2*y+ 1*z)/(x+y+z) Here, x, y and z are weight values respectively, and "weighting" means taking into account the proportional share of different variables in the population. Your quiz score is 80, and your final exam score is 90. If the teacher wants to calculate the total average score, it should be calculated according to the ratio of 40% of the quiz and 60% of the final grade, then your average score is: (80×40%+90×60%)/(40%+60%)=86 3. Someone shot it ten times. Then the average number of rings he hit is: (10 * 2+8 * 3+7 * 4+9 *1)10 = 8.1Here, the four numbers 7, 8, 9,10 are.