Find how many 3 digits odd number that can be obtained from the digit 1,2,3,4,5,6,7 if,(adsbygoogle = window.adsbygoogle || []).push({});

1/ Repetition of digits not allowed

2/ Repetition of digits allowed

my work

1/ --- the last i digit i have control 1,3,5,7

so 2 remaining digits = 6 P 2 x 4 (4ways)

= 120

2/ i AM STUCK

In fact, i don't really know whether the method is correct,i am a bit confuse, HELPPPP

ANSWER ACCORDING TO BOOKLET :

1/ 120

2/ 196

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# Homework Help: Permutation and combination homework

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