What is the probability of rolling a sum equal to a prime number when rolling a pair of dice, expressed in simplest fractional form?

What is the probability of rolling a sum equal to a prime number when rolling a pair of dice, expressed in simplest fractional form?

• A. 3/6
• B. 5/12
• C. 1/2
• D. 7/12

Answer: (B)

To find the probability of rolling a sum equal to a prime number with a pair of dice, we first identify the possible sums and then determine which sums are prime. When rolling two six-sided dice, the possible sums range from 2 (1+1) to 12 (6+6). The sums that can be obtained are: - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 Next, we identify which of these sums are prime numbers. A prime number is defined as a number greater than 1 that has no positive divisors other than 1 and itself. The prime sums from our list are: - 2 (not a valid case here as it cannot be obtained by rolling two dice) - 3 (can be rolled as 1+2 or 2+1) - 5 (can be rolled as 1+4, 2+3, or 3+2, or 4+1) - 7 (can be rolled as 1+6, 2+5, 3+4, 4+

To find the probability of rolling a sum equal to a prime number with a pair of dice, we first identify the possible sums and then determine which sums are prime.

When rolling two six-sided dice, the possible sums range from 2 (1+1) to 12 (6+6). The sums that can be obtained are:

• 2

• 3

• 4

• 5

• 6

• 7

• 8

• 9

• 10

• 11

• 12

Next, we identify which of these sums are prime numbers. A prime number is defined as a number greater than 1 that has no positive divisors other than 1 and itself. The prime sums from our list are:

• 2 (not a valid case here as it cannot be obtained by rolling two dice)

• 3 (can be rolled as 1+2 or 2+1)

• 5 (can be rolled as 1+4, 2+3, or 3+2, or 4+1)

• 7 (can be rolled as 1+6, 2+5, 3+4, 4+