Answer: There have 66.66..7% of Student own computer(s).
Step-by-step explanation:
What I did is make the whole school (270) be 100%, then I subtract from Whole school to own computer and the answer will be not own computer: 270 - 90 = 180, so there has 180 students who do not own computer, but we want to find the percentage. So we multiply 180 and 100, we will get 18,000! Then divide it to 270 and we will get 66.66..7, write it on top of 100, so it would be 66.66../100 which mean 66.66..% or 66.66..7%
Hopefully that’s helpful, if not then look the attachment include this answer to help better understanding. Good luck!
Answer:
see explanation
Step-by-step explanation:
Using the double angle identity for sine
sin2x = 2sinxcosx
Consider left side
cos20°cos40°cos80°
= (2sin20°cos20°)cos40°cos80°
= (2sin40°cos40°)cos80°
= (sin80°cos80° )
= (2sin80°cos80° )
= . sin160°
= . sin(180 - 20)°
= . sin20°
= = right side , thus proven