Answer:
250 students
Step-by-step explanation:
Given data
Let the total number of students be x
Number of students that plays instrument = 10
Hence
40% of x = 10
40/100*x= 100
0.4x=100
x=100/0.4
x= 250
Hence there are 250 students in total
Answer: x=15
Step-by-step explanation:
To solve problems like this you need to simplify the equations on both sides and then isolate your variable x.
Step 4 is wrong. the answer is 1/8, she changed sign on 2^(-3) to 2^(3) without moving it to numerator
The 90th percentile corresponds to Z ≈ 1.28155.