Answer:
A=235 cm 2
Step-by-step explanation:
A1=L x W
A1=9 x 20 180 + 55=235
A1=180cm 2
A2= L x W
A2=11 x 5
A2=55 cm2
Answer:
34 times 70
Step-by-step explanation:
9514 1404 393
Answer:
"three times a number is the same as twice the difference of the number and 1"
Step-by-step explanation:
3c is "three times a number"
2(c -1) is "two times the difference of the number and 1"
When writing the description of the right-hand side, one needs to be careful to write it so there is no ambiguity with respect to what is being multiplied by 2. For example, if you say, "two times one less than the number", it is not clear whether that is c -2×1 or 2×(c -1).
A suitable description is ...
three times a number is the same as twice the difference of the number and 1
Answer:
Step-by-step explanation:
We want to determine a 90% confidence interval for the true population mean textbook weight.
Number of sample, n = 22
Mean, u = 64 ounces
Standard deviation, s = 5.1 ounces
For a confidence level of 90%, the corresponding z value is 1.645. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean ± z ×standard deviation/√n
It becomes
64 ± 1.645 × 5.1/√22
= 64 ± 1.645 × 1.087
= 64 ± 1.788
The lower end of the confidence interval is 64 - 1.788 = 62.21 ounces
The upper end of the confidence interval is 64 + 1.788 = 65.79 ounces
Therefore, with 90% confidence interval, the true population mean textbook weight is between 62.21 ounces and 65.79 ounces
