word problem

Question

The men in your class had an average score of 60% on the last test, and the women had an average of 80%. Is the class average necessarily 70%? Explain

Answer 1

Rico,

The average score will depend on the number of men and the number of women in the classroom. Therefore, the answer is not necessarily.

1. Case 1: if the number of men and the number of women is not equal, for instance, 15 men and 20 women, the average score will be, [(15)(60%) + (20)(80%)] / (15+20)= 71.43%
2. Case 2: if the number of men and the number of women is equal, for instance, 1o men and 10 women, the average score will be, [(10)(60%) +(10)(80%)]/(10+10)= 70%.