Students at a local high school are given the option to take one gym class, one music class or one of each. Out of 100 students, 60 say they are currently taking a gym class and 70 say that they are taking a music class. How many students are taking both



Answer :

Answer:

  30

Step-by-step explanation:

You want to know the number of students of 100 that are taking both music and gym, given 60 are taking gym and 70 are taking music.

Overlap

The relation between the numbers taking music (M) and gym (G) is ...

  n(M or G) = n(M) +n(G) -n(M and G)

Then ...

  n(M and G) = n(M) +n(G) -n(M or G)

  n(M and G) = 70 +60 -100 = 30

30 students are taking both music and gym.

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Additional comment

40 are taking music only, 30 are taking gym only, and 30 are taking both, for a total of 100.