Single Probability

Probability is how likely something will happen, usually expressed as a percent. A single probability is how likely a single event will happen. To calculate a single probability, divide the number of favorable outcomes by the number of possible outcomes to get a decimal, and multiply the decimal by 100 to get a percent.
For example, a coin flip has 2 possible outcomes: heads or tails. To calculate the probability of flipping heads, do the following: 
favorable outcomes = 1
possible outcomes  = 2
decimal  = 1 ÷ 2     = 0.5
percent  = 0.5 × 100 = 50
So you would say the probability of flipping heads is 50%.

Exercise 1 of 6

What's the probability of rolling a 1 with a 6-sided die? Express as a percent, and round to two decimal places.

Exercise 2 of 6

A deck of 52 cards is divided into 4 suits: clubs, diamonds, hearts, and spades. Each suit has 13 ranks: the numbers 2-10, jack, queen, king, and ace. What's the probability of drawing a spade from a deck of cards?

Exercise 3 of 6

A face card is a jack, queen, or king. What's the probability of drawing a face card from a deck of cards?

Exercise 4 of 6

In the game Battleship, players place ships on a 10×10 grid. Each ship's size determines the number of squares it will occupy, and ships cannot overlap. Each player has a carrier of size 5, a battleship of size 4, a cruiser of size 3, a submarine of size 3, and a destroyer of size 2. Players cannot see each other's grid, and each turn, a player calls out a square to fire at. What's the probability of hitting a ship on the first turn?

Exercise 5 of 6

In the game show Wheel of Fortune, contestants spin a wheel with 24 wedges. One wedge is labeled Lose a Turn, and two are labeled Bankrupt. The rest are various dollar amounts and prizes. What's the probability of landing on a dollar amount or prize?

Exercise 6 of 6

What's the probability of rolling doubles with two 6-sided dice? Said another way, what's the probability of the second die matching the first die?

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