This can be solved using the formula for t test which is = x - mu over standard deviation divided by the square root of the number of samples. In this case, it is 1185 - 1200 over 70 divided by square root of 100 which give us a value of 2.14 which is equal to .9839 in area. Only rarely, just over one time in a hundred tries of 100 light bulbs, would the average life exceed 1200 hours.
The answer in this question is 97.
0.20 SD = 1.96 SD / sqrt(n)
n = (1.96 / .200)^2
n = 96.04
Which is rounded Up to 97
The number of observations within the data set must be greater than or equal to the quantity of 97.
We have this following information
30-seconds ad = $146000
The manufacturer wants to use one slot of 30-second per segment
Total segment = 20 segment
Total campaign cost = 20×146000 = $2,920,000
Answer How many liters of a 20% acid solution should be mixed with 30 liters of 50% acid solution in order to obtain a 40% solution. ... x=15 liters 15*(.20 pure acid)=3 liters 30*(.50 pure acid)=15 liters That is 18 liters pure acid That is 45 liters solution *0.45 pure acid=18 liters.
Step-by-step explanation: