The greatest common factor of 18k and 15k is 3k.
5k
5k
3k
3k
With appropriate training, you may be able to run a 15K.
It means kilo which is 1000 and 15k is 15*1000 = 15000
15,000
15k simply means 15,000, 15Kbps would be 15,000 bits per second
Therefore 15k is 15 times 3 = 45
$15K
15000 ...