We need the total count of persons = 10+12+12+15 = 49 persons
We need the count of the target group, female or teaching assistants
= (10+12) professors + 12 male teaching assistants
= 22+12
= 34 persons
Assuming equal probability of choosing anyone from the 30 persons, the
probability of choosing a professor or a male
= 34/49
(For probability calculations, try to keep a fraction for as long as you can, because fractions are exact. Decimal are frequently approximate, for example in this case, 34/49=0.693877551020...... = 0.694 approximately)
Perfectly correct. Two quarters do make a half :)
<u>8th Grade: </u>90 x 0.80 = 72
<u>7th Grade:</u> 80 x 0.75 = 60
Conclusion: 8th Graders like pop music more because 72 out of the 90 in 8th grade Dave surveyed enjoy it, compared to the 60 out of 80 in 7th grade that enjoyed it.
23 lines × 5 trees= 115 tree. or. 5 lines × 23 trees = 115 trees
The percent of decrease on an item that went from $25 to $20 is 5 percent.