Represent these consecutive numbers (assuming that they are all integers):
x
x+1
x+2
x+3
x+4
x+5
and so on
x+8
x+9 is the tenth number. x+9 = 10, so x = 9.
Think of it this way: there are 10 consecutive numbers, and the last one is 10.
Working backwards, we get the sequence 10, 9, ... 3, 2, 1.
The sum of such an arith sequence is equal to the count of the numbers times the average of the first and last terms:
sum here = 10(1+10)/2 = 5(11) = 55 (answer)
Answer:
c. Cluster sampling
Step-by-step explanation:
Taking into account that the exercise researcher is looking with limited resources to study a population that is divided, her best option is cluster sampling, which is a method applicable to this type of population, we could select in each group randomly her sample, the observational study is discarded because she does not have much availability of time or resources, nor would the stratified study be useful because she should select subgroups and create them to take samples and this would take more time and resources and sampling systematic is not adequate because it must have all the individuals and after having the list select the sample, but as we know, it is a process that will study the number of individuals so this option is not feasible.
Answer:
35.
Step-by-step explanation:
To find the area, multiply the length and the width.
A = L x W
7 x 5 = 35
subtract the fee from the total to get the amount actually spent on songs
23.80-7 = 16.80
divide that amount by price per song to get number of songs downloaded
16.80 /0.20 = 84 songs
It's the graphs that don't touch the x-axis have complex roots. Roots are the points where the parabola touches the x-axis. A,C and E all cross/touch the x-axis so they have real roots.
non-real or complex root parabolas are: B, D, F
