Solve the problem by methods of proportion.
b. In a hostel 50 students have food enough for 32 days. How many students should be leave the hostel so that the food is enough for 40 days.
C. A work is compete in 24 days working 8 hours per day. How many days are there required to complete the same work working 6 hours per day?
d. 20 goats can graze grass of a land in 12 days. How many goats can graze the grass of same land in 15 days?​