nr321501 Operations Research
nr321501 Operations Research
nr321501 Operations Research
1. A Caterer is to organize garden parties for a week. He needs a total of 160, 120, 60,
90, 110, 100 and 120 fresh napkins during the seven days of the week. Each new
napkin costs Rs. 3. He can use soiled napkins after getting them washed from a
laundry. Ordinarily, washing charges are Rs.0.6 per napkin and they are returned
after four days. However, the laundry also provides express service, at a cost of
Rs.1 per napkin, in which case they are returned after two days. Determine the
planning schedule the caterer should adopt to buy or send napkins to the laundry
so as to minimize the cost. [16]
D1 D2 D3 D4 D5 Availability
O1 4 7 3 8 2 4
O2 1 4 7 3 8 7
O3 7 2 4 7 7 9
O4 4 8 2 4 7 2
Demand 8 3 7 2 2 22
3. A Company has four territories open and four salesman available for assignment.
The territories are not equally rich in their sales potential, it is essential that a
typical salesman operating in each territory would bring in the following annual
sales :
Territory I : Rs. 60,000
Territory II : Rs. 50,000
Territory III : Rs. 40,000
Territory IV : Rs. 30,000
The four salesmen are also considered to differ in ability; it is estimated that,
working under the same conditions, their yearly sales would be proportionately as
follows :
Salesman A : 7 ; Salesman B : 5 ; Salesman C: 5 ; Salesman D : 4
If the criterion is maximum expected total sales, the intuitive answer is sto assign
the best salesman to the richest territory, the next best salesman to the second
richest territory and so on. Verify this answer by the assignment method. [16]
4. A series lamp circuit contains 10,000 bulbs. When any bulb fails, it is replaced.
The cost of replacing a bulb individually is Re.1 only. If all the bulbs are replaced
simultaneously, the cost per bulb would be Re.0.35. The percent of surviving, say
s(t) at the end of the month ‘t’ and p(t) probabilities of failure during the month
are given below:
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Code No: NR321501 NR
t 0 1 2 3 4 5 6
s(t) 100 97 90 70 30 15 0
p(t) - 0.03 0.07 0.20 0.40 0.15 0.15
what is the optimal replacement? [16]
7. (a) List and explain different types of costs incurred in inventory system.
(b) The annual demand for an items is 3200 units, the unit cost is Rs. 6/- and
inventory charges 25% per annum. If the cost of one procurement is Rs. 150/-,
Determine
i. Economic Order Quantity
ii. Number of orders per year
iii. Time between two consecutive orders
iv. the optimal cost. [6+10]
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Code No: NR321501 NR
ii. State variable
iii. Immediate return
iv. Optimal return . [8+8]
?????
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