The amount invested is $ 470
<h3><u>Solution:</u></h3>
Given that , we have earned $131.60 as simple interest for an amount deposit at the rate of 4% for seven years.
We have to find the amount invested. That is, we need to find the principal sum
Let us use the simple interest formula
<em><u>The simple interest is given as:</u></em>
Here, simple interest = $ 131.60
Rate of interest = 4 %
Number of years = 7
principal = ?
Substituting the values in formula, we get
Thus the amount invested is $ 470
There was 3 erasers in each pack because 2 times 3 is 6 plus 2 equals 8. so there are 3 in each pack.
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.
A. $7.40
Adding $3.14 to $0.67 equals $3.81
You then could add $2.45 to $3.81 and get $6.26
Finally you add $1.14 to $6.26 and get $7.40
