Answer:
a. 5i + 13j
b. 8i
c. 10i + 6j
Step-by-step explanation:
a. 2i + 6j + 3i + 7j = 5i + 13j
b. 3i + 7j + 5i - 7j = 8i
c. 2i + 6j + 3i + 7j + 5i - 7j = 10i + 6j
Answer:
28 quarters and 12 nickles
Step-by-step explanation:
How many quarters goes into 7 dollars? 28, because there is 4 in each dollar.
How many nickles are in 60 cents? 12, because 5 times 12 is 60.
$17.49 because you multiply 22 by .25 getting 5.5. You subtract that from the original 22 getting 16.5 which you then multiply by the sales tax .06. Add the tax amount to the 16.5 to get 17.49.
The confidence interval would be (10.44, 12.16). This means that if we take repeated samples, the true mean lies in 90% of these intervals.
To find the confidence interval, we use:

We first find the z-value associated with this. To do this:
Convert 90% to a decimal: 90% = 90/100 = 0.9
Subtract from 1: 1-0.9 = 0.1
Divide by 2: 0.1/2 = 0.05
Subtract from 1: 1-0.05 = 0.95
Using a z-table (http://www.z-table.com) we see that this is directly between two z-scores, 1.64 and 1.65; we will use 1.645: