18.11 Mathematical methods and models in economics

Problem: 11 workers produce products in a workshop. The productivity of the \( i-t h \) worker is equal to \( 1+0,1(i-1) \mathrm{kg} \) of production per hour, \( i=1, \ldots, 11 \). Each worker has produced \( 7 \mathrm{~kg} \) of products. Determine the total working time of all workers of the workshop and the labour productivity of the whole workshop.