Answer : The number system based on shale is called hexadecimal number system. The number in hexadecimal number system is 18. It is common practice to form and express hexadecimal numbers using six capital letters in English with ten digits in decimal or decimal number system. The 16 digits of the hexadecimal number system are 0 , 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , A, B, C, D, E, F. The hexadecimal number system is not well known to the general public. However, hexadecimal numbers are used in computer systems. The biggest advantage of this is that the hexadecimal number system requires 2 hexadecimal numbers to express one byte.