Question

how many odd numbers less than 400,000 are there that involve all of the digits 1, 1, 2, 3, 5 and 6

Answer 1

2n-1<400 000
2n<400 001
n<200000.5
all odd less than 400000 are 200000

Answer 2

the last one is 399999

Answer 3

the number has to be 6 digits to have then all

Answer 4

hence the numbers are between 300001 and 399999

Answer 5

3112346 not odd
we cant end with 2,4,6 so
possibilities are 4
3___426
3___462
3___264
3___624

Answer 6

3___246
3___642
this makes total 6

Answer 7

6 ways of arranging 3 numbers
\[6 \times 3!=36\]

Answer 8

i give up they are tricking me now
@Hero @phi