Step-by-step explanation:
sum of the arithmetic sequence
a1 = 8
a2 = a1 + 8 = 8+8 = 16
...
an = 8×n
the sum of the first n elements of such a series is
n/2 × (2×a1 + (n - 1)×d]
with d being the difference between 2 consecutive elements (= the added constant).
so,
s30 = 30/2 × (2×8 + 29×8) = 15×(31×8) = 3720
Answer:
1) +80
2) -1520
Step-by-step explanation:
Positive Signed numbers are used in real world situations to indicate the increase. Examples include; increase in weight, deposit of money into an account, increase in income, profit, height above sea level, etc. They are all represented by positive signed numbers.
Whereas, negative signed numbers show decrease. Examples include; loss of weight, withdrawal of money from an account, loans, liabilities, losses, temperature below zero degrees, height below sea level.
1) We are told that Reuben received 80 dollars. Thus, it means he received an increase in the amount of money he already had. Thus, the signed number will be +80.
2) We are told that A car corporation produced 1520 fewer cars this month than last.
Thus, the signed number will be negative since there is a decrease in number of cars.
Thus, signed number = -1520
I think the answer will be A
Answer:
The expected frequency for people against the project and who have over 120 feet of property foot frontage is 3.9.
Step-by-step explanation:
The data provided is:
Opinion
Front Footage For Undecided Against Total
Under 45 feet 12 4 4 20
45-120 feet 35 5 30 70
Over 120 feet 3 2 5 10
Total 50 11 39 100
The formula to compute the expected frequency is:
Compute the expected frequency for people against the project and who have over 120 feet of property foot frontage as follows:
Thus, the expected frequency for people against the project and who have over 120 feet of property foot frontage is 3.9.
<span>So we need to see how does the decimal point change it's place in the quotient when we divide any number by increasing powers of 10. Lets start with number 1. The decimal point is: 1.0 and when we divide by 10^1=10 we get 1/10=0.1. The decimal point has moved one place to the left. Now lets divide 1 by 10^2 and we get 1/100=0.01. Again, the decimal point has moved one more place to the left. Now: 1/10^3 = 1/1000 = 0.001. Next would be 0.0001, next one would be 0.00001 and so on. </span>
