PROMPT ANALYSIS
Let total number of device be T
CPU = 2T/17
Motherboard = 3T/17
Keyboards = 5T/17
Mouse pad = 7T/17
SUPERSET
T will a natural number multiple of 17.
TRANSLATION
In order to find T:
1# we need exact value of T
2# another equation with T as variable.
Statement Analysis
St 1: Since T/17 will yeild an integer, 5T/17 will also be an integer.Between 6 and 14, only 10 is a mutiple of 5. Hence no. of keyboards =10. No. of motherboards = 6 and T =38. Therfore the difference is 4.ANSWER. Option b,c and e eliminated.
St 2: 7T/17 -2T/17 = 10 or 5T/17 = 10 or T=38. Hence no. of keyboards =10. No. of motherboards = 6. Therfore the difference is 4.ANSWER. Option a eliminated.
Option D
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