35 students would not know any of the three languages, because if 30 know French, 19 knew German, and 16 knew Russian, that must mean that 65 students know at least one of the three languages. So you subtract 65 from 100 and end up with 35
Answer:
1,5
Step-by-step explanation:
80y² - 5x²
Factorise
5(16y²-x²)
hope this helps
divide out any similar things, in this case, it is 5
put it outside the parenthesis, and leave the leftover inside the parenthesis
hope this helps
Answer:
38%
Step-by-step explanation:
Given that X,the hours per week the music student practice follow a normal distribution.
X:N(8,4)
We have to find the percentage of students who practice between 6 and 10 hours.
6<x<10 implies converting to z
We know z = (x-mean)/sigma = (x-8)/4
Hence 6<x<10 is equivalent to (6-8/4)<Z<(10-8/4)
= |z|<0.5
From std normal table we find this area equals = 0.1915+0.1915
=0.3830 = 0.38 (rounded off)
Hence required percentage = 0.38x100 = 38%
