this probability distribution shows the typical distribution of pitches thrown to a batter in a given at-bat in a baseball game. Find the probability that the pitcher will throw 4 or fewer pitchers to a batter.

Answer = 9/10

Explanation:

Add up all the frequencies along the bottom row: 15+20+40+15+10 = 100

There are 100 pitches total. Ten of which occurs when the pitcher throws 5 times at the batter, as shown in the far right-most column. This means 100-10 = 90 occurrences happen when the pitcher throws 4 or fewer pitches to the batter.

The probability your teacher wants is therefore 90/100 = 9/10. This answer is in fraction form. It is equivalent to the decimal form 0.9

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so:

step-by-step explanation: