English translation:
If the quality control manager wants to estimate the average life of lamps with 20 hours, with a confidence level of 95% and an error of 10% is assumed. What is the sample size?
57,142 because it says standard
Let a =107° and b=42°;
So cos 107° cos 42° + sin 107° sin 42° = cosa.cos42 + sina.sinb = cos(a-b)
and cos 107° cos 42° + sin 107° sin 42° = cos(107-42) = cos(65°)
16x
Both of these expressions are similar expressions, therefore you can simply add the number in front of the 'x'
6 + 10 = 16
Therefore, 6x + 10x = 16x
Answer:
The correct answer is C. 13
Step-by-step explanation:
It is 13 because all triangles equal 180
so 125+42+13=180
