There are 40 balls which are red, blue or green. If 15 balls are green and the sum of red balls and green balls is less than 25, at most how many red balls are there? Select the correct option:
A) 4 B) 5 C) 6 D) 7 E) 9
r+g+b=40   g=15   r + g &lt; 25   =&gt; r + 15 &lt; 25   =&gt; r &lt; 10   =&gt; at most 6 red balls   ANSW9R:9
<result>E</result>
There are 40 balls which are red, blue or green. If 15 balls are green and the sum of red balls and green balls is less than 25, at most how many red balls are there?