Task Statistics #8

Task Statistics #8

Task 1
When studying the influence of advertising on the size of the average monthly deposit in the banks of the region, 2 banks were examined. The following results are obtained:
Monthly deposit amount, rubles Number of depositors
Bank with ads Bank without ads
Up to 500 ----- 3
500-520 ----- 4
520-540 ----- 17
540-560 11 15
560-580 13 6
580-600 18 5
600-620 6 -----
620-640 2 -----
Total 50 50
Define:
1) for each bank: a) average monthly deposit; b) dispersion of the contribution;
2) the average monthly deposit for two banks together.
3) Dispersion of the deposit for 2 banks, depending on advertising;
4) Dispersion of the deposit for 2 banks, depending on all factors except advertising;
5) Total variance using the addition rule;
6) Coefficient of determination;
7) Correlation relation.

Additional information:

5) Total variance using the addition rule;
6) Coefficient of determination;
7) Correlation relation.