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Find the multiplicative inverse of 8-12i

How many different three-digit numbers can be formed using the digits 1 comma 2 comma 9 comma 6 comma 4 comma 3 comma and 8 without repetition? for example, 664 is not allowed.

Convert the number to decimal form. 12) 312five a) 82 b) 30 c) 410 d) 1560 13) 156eight a) 880 b) 96 c) 164 d) 110 14) 6715eight a) 53,720 b) 3533 c) 117 d) 152