A baker makes chocolate cookies and peanut cookies. His recipes allow him to make chocolate cookie in batches of 7 and peanut cookies in batches of 6. If he makes exactly 99 cookies, what is the minimum number of chocolate chip cookies he makes?  Answers:	A) 7	B) 14	C) 21	D) 28	E) 35
7C+6P=99   We need to maximize P to minimize C so that the eq is also satisfied   Try substitution for CP to solve so that eqn is satisfied   The least value of C for which equation gets satisfied is 5   i.e. 7*3+6*13=21+78= 
<gadget id="calculator">21+78</gadget>
<output>99</output>
99   Hence 21 is the answer
<result>C</result>
A baker makes chocolate cookies and peanut cookies. His recipes allow him to make chocolate cookie in batches of 7 and peanut cookies in batches of 6. If he makes exactly 99 cookies, what is the minimum number of chocolate chip cookies he makes?