### Instruction: The Grunters play the Screamers 4 times.  The Grunters are the much better team, and are $75\%$ likely to win any given game.  What is the probability that the Grunters will win all 4 games? Express your answer as a common fraction.### Response: To find the probability of two independent events happening, I can multiply their individual probabilities.
So, the probability of the Grunters winning the first game is $0.75$, and the probability of them winning the second game is also $0.75$, regardless of the outcome of the first game.
Therefore, the probability of the Grunters winning the first two games is $0.75 \times 0.75 = 0.5625$.
Similarly, the probability of the Grunters winning the third game is $0.75$, and the probability of them winning the fourth game is $0.75$, no matter what happened in the previous games.
Hence, the probability of the Grunters winning all four games is $0.5625 \times 0.75 \times 0.75 = 0.3164$.
This is a decimal, but the question asks for a common fraction.
I can convert a decimal to a fraction by writing it over a power of 10 and simplifying.
For example, $0.3164 = \frac{3164}{10000}$.
To simplify this fraction, I can divide both the numerator and the denominator by the greatest common factor of 3164 and 10000, which is 4.
So, $\frac{3164}{10000} = \frac{3164 \div 4}{10000 \div 4} = \frac{791}{2500}$.