Let's figure this out as though we have no idea what the answer would be.
Step One
Find the new five numbers.
3*3, 8*3, 12*3, 17*3, 25*3
9 , 24 , 36, 51, 75
Step 2
Find the average
(9 + 24 + 36 + 51 + 75)/5 = 195/5 = 39
Step 3
Subtract the individual numbers from the average
(39 - 9) = 30
(39 -24) = 15
(39 - 36) = 3
(39 - 51) = - 12
(39 - 75) = -36
Step 4
Square the results from Step 3
30^2 = 900
15^2 = 225
3^2 = 9
(-12)^2 = 144
(-36)^2 = 1296
Step 5
Take the average of the results from step 4
(900 + 225 + 9 + 144 + 1296)/5
2574 / 5 = 514.8
Step 6
Take the square root of the result from step 5
deviation = sqrt(514.8)
deviation = 22.689
Step seven
Compare the two standard deviations.
s2/s1 = 22.689 / 7.563 = 3
Conclusion
If you are given 1 set of numbers to find a population standard deviation and you multiply each member by a, then the result will be a * the standard population deviation of the first set of numbers.
Note
Your calculator will do this as well, but you have to know how to enter the data into your calculator. That requires that you follow the directions carefully.
Answer: where is it?
what do u mean??? im confused...
You do the following.
Take the price of the most expensive subscription and retract the price of the cheap one.
$50-$40 = $10
Since we know what the price of a text message and the difference in dollars between the two subscriptions, we can calculate how many text messages has to be sent. We just divide the result from before ($10) with the price of a text message ($0.2)
$10/$0.2 = 50
The total number of text messages that needs to be send in order for the price of the subscriptions to be the same, is 50.
15:15
Which is simplified to
1:1
Hope this helps!
X/9=1
Multiply both sides by 9. So x=9.
