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?
Step 1: -12x - 2y ≥ -42
Step 2: -2y ≥ -12 - 42
Step 3: y ≤ -6x + 21
So the answer is
D) <span>y ≤ -6x + 21</span>
Putting the dot points is the second
15 + 1 = x/6
16 = x/6
16 * 6 = x
x = 96
Answer: A)
Answer:
Elena invested $ 1,700 at 5%, $ 700 at 4%, and $ 600 at 3%.
Step-by-step explanation:
Given that Elena receives $ 131 per year in simple interest from three investments totaling $ 3000, and part is invested at 3%, part at 4% and part at 5%, and there is $ 1000 more invested at 5% than at 4%, to find the amount invested at each rate, the following calculations must be performed:
1500 x 0.05 + 500 x 0.04 + 1000 x 0.03 = 75 + 20 + 30 = 125
1600 x 0.05 + 600 x 0.04 + 800 x 0.03 = 80 + 24 + 24 = 128
1700 x 0.05 + 700 x 0.04 + 600 x 0.03 = 85 + 28 + 18 = 131
Therefore, Elena invested $ 1,700 at 5%, $ 700 at 4%, and $ 600 at 3%
