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3 votes
Erin's playlist includes rock songs and

lyric songs. There are 18% more rock
songs than lyric songs. What is the
probability that a randomly chosen song to
listen to will be lyric?

1 Answer

4 votes

Answer:

0.459 or 45.9%

Explanation:

Let R be the number of rock songs on Erin's playlist.

Let L be the number of lyric songs on Erin's playlist.

Given that there are 18% more rock songs than lyric songs, this can be expressed as:


R = L + 0.18L


R = 1.18L

Now, the total number of songs in Erin's playlist is the sum of the lyric songs and the rock songs:


\text{Total songs} = L + R

Substitute R = 1.18L into the equation to find the total number of songs in terms of lyric songs (L):


\begin{aligned}\text{Total songs} &= L + R \\&= L + 1.18L \\&= 2.18L\end{aligned}

The probability of randomly choosing a lyric song is given by the ratio of the number of lyric songs to the total number of songs:


P(\text{Lyric}) = (L)/(2.18L)

Simplify the fraction:


P(\text{Lyric}) = (1)/(2.18)

Now, calculate the probability:


P(\text{Lyric}) =0.45871559633...


P(\text{Lyric}) =0.459\;\rm (3\;s.f.)

Therfeore, the probability that a randomly chosen song will be a lyric song is approximately 0.459, or 45.9%.

User Zuloo
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