Practice30Create account

A player throws a pair of fair dice and compares two totals: the two numbers added, and the two numbers multiplied. What is the probability that adding gives the strictly bigger result?

Competition practiceProbability & Permutation
  • A11/36
  • B1/3
  • C1/6
  • D5/18

Step-by-Step Solution

If either die shows 1 the sum wins: 1 + b is always bigger than 1 × b. That covers the 6 throws with the first die 1 and the 6 with the second die 1, but (1,1) sits in both lists, so it is 6 + 6 − 1 = 11 throws. With both dice at 2 or more the product never falls behind, since ab − (a + b) = (a − 1)(b − 1) − 1 ≥ 0. So 11 throws out of 36. Trap 1/3 = 12/36 also counts (2,2), where sum and product both equal 4 — 'strictly greater' rules a tie out. Trap 1/6 counts only the throws whose FIRST die is 1. Trap 5/18 = 10/36 subtracts the shared throw (1,1) twice.
Answer: A) 11/36

Master this topic in 30 minutes a day.

Don't just memorise the answer — build a daily practice habit.

Practice 5 Similar Questions Free →

All Probability & Permutation practice questions

More Probability & Permutation practice

Three fair dice are rolled together. What is the probability that no two of the three…Two fair dice are thrown and a friend reports, truthfully, that the two dice did NOT…A dealer shuffles a 52-card pack and turns up two cards at the same time. What is the…A player deals himself three cards off the top of a shuffled 52-card pack. What is the…From a shuffled 52-card pack, two cards are lifted out at one go. What is the…