Here's the question you clicked on:
watermelon26
You are rolling two dice at the same time. What is the probability of rolling a sum of 6 or 7?
what do you mean by sum of 6 and 7? two 6 or two 7?
\[P(6\cup7)=P(6)+P(7)-P(6n7)\]
Dice 1 2 3 4 5 6 1 2 3 4 5 6 7 2 3 4 5 6 7 8 3 4 5 6 7 8 9 4 5 6 7 8 9 10 5 6 7 8 9 10 11 6 7 8 9 10 11 12 now in this 6 comes 5 times and 7 comes 6 times and total sample space is 36 so probability of 6or,7 is 11/36