Sin 20° · sin 40° · sin 80° = 1/2 ( cos 20° - cos 60° ) · sin 80° =
= 1/2 ( cos 20° sin 80° - cos 60° sin 80° ) =
= 1/2 ( (sin 100° + sin 60°)/2 - 1/2 sin 80° )= ( sin 100° = sin 80° )
= 1/2 · ( 1/2 sin 60° ) = 1/4 sin 60° = √3 / 8
sin 60° = √ 3/2
√ 3 / 2 · √ 3 / 8 = 3/16 ( correct )
Answer: 
Step-by-step explanation:
Given : Total number of students who are asked to complete a survey anonymously : n= 240
Number of students
The proportion report that they have experienced bullying =54
Then , the proportion that students have experienced bullying =
Significance interval : 
Critical value : 
The confidence interval for the true proportion is given by :-

Answer:
20:36
Step-by-step explanation:
to simplify a fraction you must divide both top and bottom by the same number and 20:36/ 4 equals 5:9
-2x+14y=148*3x+5y=256
(-2x+14y)/148=3x+5y=256/148
(-x+y)37/7=3x+5y=64/37
37*7(x+y)/37=(3x+5y)*37=64/37*37
7(x+y)=111x+185y=64
7x-111x=-7y-185y+64
104x=191y+64
x=191y+64/104