(i) A shopping mall allows customers to shop using, cash or credit card of any nationalised bank. It awards bonus points to their customers on the basis of criteria given below:
- The customer is an employee of the shopping mall and makes the payment using a credit card
OR
- The customer shops items which carry bonus points and makes the payment using a credit card with a shopping amount of less than Rs 10,000/-
OR
- The customer is not an employee of the shopping mall and makes the payment not through a credit card but in cash for the shopping amount above Rs 10,000/-

The inputs are:
C - Payment through a credit card
A - Shopping amount is above Rs 10,000/-
E - The customer is an employee of the shopping mall
I - Item carries a bonus point

(In all the above cases, 1 indicates yes and 0 indicates no.)
Output: X [1 indicates purchased, 0 indicates not purchased for all cases]
Draw the truth table for the inputs and outputs given above and write the POS expression for X (C, A, E, I).

(ii) Differentiate between half adder and full adder. Write the Boolean expression and draw the logic circuit diagram for the SUM and CARRY of a full adder.

(iii) Verify the following expression by using the truth table:
(A ⊙ B)' = (A ⊕ B)

Solution

(i)

(ii)

(iii)