Question

Problem 12-3:

The following table lists the components needed to assemble an end item, lead times (in weeks), and quantities on hand.

Item		Lead Time	Amount on Hand			Direct Components
End		3		0		L(2), C(1), K(3)
L		3		9		B(2), J(3)
C		4		14		G(2), B(2)
K		4		19		H(4), B(2)
B		3		27
J		4		32
G		4		5
H		2		0

a. If 43 units of the end item are to be assembled, how many additional units of B are needed? (Hint: You don’t need to develop an MRP plan.)

Additional units           

b. An order for the end item is scheduled to be shipped at the start of week 15. What is the latest week that the order can be started and still be ready to ship on time? (Hint: You don’t need to develop an MRP plan.)

The latest week           

Answer 1

43 units of end items are to be shipped

Therefore , gross number of item L required = 43 x 2 = 86

Number of L items on hand = 9 units

Therefore , net amount of L items required = 86 – 9 = 77

Since 2 number of item B required for each unit of L , number of item B required = 77 x 2 = 154

Since 1 unit of item C is required for each unit of end items,

Gross number of item C required for 43 units of end item = 43 units

Amount of item C on hand = 14

Therefore, net number of item C required = 43 – 14 = 29 units

Since 2 number of item B required for each unit of C,

Number of item B required = 29 x 2 = 58 units

Since 3 units of item K required for each unit of end item,

Gross number of item K required for 43 units of end item = 43 x 3 = 129

Number of item K in hand = 19 numbers

Therefore, net requirement of item K = 129 – 19 = 110

Since 2 units of item B required for each unit of item K , gross number of item K required = 110 x 2 = 220

However, number of item B in hand = 27 units

Therefore , net number of item B required = 220 – 27 = 193 units

Hence, total number of item B required = 154 + 58 + 193 units = 405 units

ADDITIONAL UNITS OF ITEM B REQUIRED = 405 UNITS

Time lag in delivery time between end item and B

= Lead time of delivery of C/K + lead time of delivery item B

= 4 + 3 weeks

= 7 weeks

Time lag in delivery time between end item and G

= Lead time of delivery of C + Lead time of delivery of G

= 4 + 4

= 8 weeks

Time lag in delivery between end item and J

= Lead time of delivery of L    + Lead time of delivery of J

= 3 + 4

= 7 weeks

Time lag in delivery between end item and H

= Lead time of delivery of K + Lead time of delivery H

= 4 + 2

= 6 weeks

Therefore , highest lead time of delivery for first level inputs vis a vis delivery time of end product = 8 weeks ( item G )

Since end item is required at beginning of week 15 ,

Input item is to be delivered latest by = 15 - 8 = 7 weeks

THE LATEST WEEK = 7 WEEKS