There are 400 wolfs at a large zoo. The number of wolfs is 4 times the number of all the other animals combined. How many more wolfs are there than non wolfs animals at the zoo?	Choose the correct choice from the following.
A) 450 B) 420 C) 400 D) 390 E) 350
Answer is D.   Total wolfs= 400 = 4 * Other Animals (X)   or X = 10.   So, 390ifference in wolfs and X = 400-10= 
<gadget id="calculator">400-10</gadget>
<output>390</output>
390.
<result>D</result>
There are 400 wolfs at a large zoo. The number of wolfs is 4 times the number of all the other animals combined. How many more wolfs are there than non wolfs animals at the zoo?