The numbers {1, 3, 6, 7, 7, 7} are used to form three 2-digit numbers. If the sum of these three numbers is a prime number p, what is the largest possible value of p?
Choose the correct answer:  A) 97  B) 151  C) 209  D) 211  E) 219
What is the largest possible sum of these three numbers that we can form? Maximize the first digit: 76+73+71= 
<gadget id="calculator">76+73+71</gadget>
<output>220</output>
220=even, so not a prime. Let's try next largest sum, switch digits in 76 and we'll get:  67+73+71= 
<gadget id="calculator"> 67+73+71</gadget>
<output>211</output>
211=prime.   Answer: 211.
<result>D</result>
The numbers {1, 3, 6, 7, 7, 7} are used to form three 2-digit numbers. If the sum of these three numbers is a prime number p, what is the largest possible value of p?