A cement plant planned to produce a batch of cement in January. In fact, it completed one third of the plan in the first ten days, two fifths of the plan in the middle ten days, and another 26 tons in the last ten days. As a result, it exceeded one sixth of the plan. How many tons of cement are planned to be produced in January?

A cement plant planned to produce a batch of cement in January. In fact, it completed one third of the plan in the first ten days, two fifths of the plan in the middle ten days, and another 26 tons in the last ten days. As a result, it exceeded one sixth of the plan. How many tons of cement are planned to be produced in January?

Answer 26 / (1 + 1 / 6-1 / 3-2 / 5) = 60 tons