Answer:

Step-by-step explanation:
As the numbers are only between 1 and 30
Total number of possible combinations = 30×30×30 = 27000
If there are 100 attempts then

∴ Probability someone can guess the correct combination given 100 attempts is 
Answer: 0
Step-by-step explanation:
Answer:
7/12
1/6 to 2/12 add 5/12 to get 7/12
Step-by-step explanation:
5(tanx)^2 -2 +tanx=0
let tanx=y
5y^2 + y-2=0
y=0.5403 or y= -0.7403
tanx=0.5403
x=arctan(0.5403)
x=28.38°
or
tanx=-0.7403
x=arctan(-0.7403)
x=143.49°
The Answer For Number Two Is Negative 14