What's the issue ?

1 1. The first two columns of the accompanying table provide a frequency distribution, using limit grouping, for the days to maturity of 40 butterflies. The third column shows the class marks. Use the grouped-data formulas to estimate the sample mean of the butterfly days-to-maturity. (Do not round.) Page 2 of 3 RVCC Statistics I Homework Days to Frequency Class mark maturity X 30-39 34.5 10-49 44.5 50-59 54.5 60-69 64.5 70-79 74.5 80-89 84.5 90-99 94.5 12. An entrepreneur faces many bureaucratic and legal hurdles when starting a new business. The following is sample of 25 countries from data on the time, in days, to complete all the procedures required to start a business. 13 66 - 36 12 8 27 6 5 52 48 15 7 12 94 28 13 60 5 18 294 Use the data above to calculate the sample mean. (Do not round.) 13. Twenty lab rats are taught to push a lever in their cage to drop a food pellet. For 10 days, the rats learn to push the lever and, each time, a food pellet drops. On the 1 1th day, the researchers remove the food pellets, but keep the lever in the cage. The number of times each rat pushes the lever on the 1 1th day is recorded for each rat and displayed in the histogram below. 10 Frequency of Pushes 4 5 6 7 8 9 10 1 1 12 13 14 Pushes Calculate the mean for the number of pushes on the 1 1th day. (Do not round.)