<p>If j, k and n are consecutive integers such that 0< j<k< n and the units (ones) digit of the product jn is 9, what is the units digit of k
a) 0
b) 1
c) 2
d) 3
e) 4</p>
<p>The anwser is A , but i still do not understand how its A...isnt j less than k.</p>
<p>well its asking for the unit digit (the ones), so its not necessarily, asking for the value of the entire number, get it?</p>
<p>Here's an example:</p>
<p>j = 19
k = 20
n = 21</p>
<p>jn = 399</p>
<p>And the units digit of k is 0.</p>
<p>Ahhhhh!!! Thanks Alot!</p>