An intelligence agency decides on a code of 2 digits selected from 0, 1, 2, , 9. But on the slip on which the code is hand written allows confusion between top and bottom, because there are indistinguishable. Thus, for example, the code 91 could be confused with 16. How many codes are there such that there is no possibility of any confusion
Answers
Answer:
7 Such possible combination
Step-by-step explanation:
An intelligence agency decides on a code of 2 digits selected from 0, 1, 2, , 9. But on the slip on which the code is hand written allows confusion between top and bottom, because there are indistinguishable. Thus, for example, the code 91 could be confused with 16. How many codes are there such that there is no possibility of any confusion
0 , 1 , 9 will Create confusion
but when 2 is used its clear from which side is top & which is bottom
so 2 must be included in code
Posssibilites
1st digit is 2 -> 2nd Digit Can be Any Digit (4 )
ist digit is any digit other than 2 -> 2nd digit is 2 (3)
4 + 3 = 7
7 Such possible combination
20
21
22
29
02
12
92
Answer:
80
Step-by-step explanation:
The digits which can create confusion in top & bottom are 0, 1, 6, 8, 9.
Total two-digit confusing codes = 5 × 5 = 25.
But 00, 11, 88, 69, 96 don’t change their value in both the cases.
So, these five do not come in category of confusing code.
Total confusing code number = 25 – 5 = 20.
Total non – confusing code of two digits = 100 – 20 = 80.