Aclassroom has stadium. there are 10 seats in the first row, 13 seats in the second row, 16 seats in the third row and so on. there are 56 rows what is the seating capacity of the class?

the classroom has 4,900 seats.

the classroom has 5,180 seats.

the classroom has 4,995 seats

the classroom has 5,348 seats

B

5180

Step-by-step explanation:

a1 = 10

n = 56

d = 3

L = a1 + (n - 1)*d

L = 10 + 55*3

L = 10 + 165

L = 175

Sum = (a1 + L)*n/2

Sum = (10 + 175)*56/2

Sum = 185 * 56/2

Sum = 185 * 28

Sum = 5180

The answer is B

where is the figure

step-by-step explanation:

i found the life tables for the year 2012. 

life table of males at age 30. probability of dying between ages x and x+1

total population:  

29–30 . . . . . . . . . . . . 0.001030

30–31 . . . . . . . . . . . . 0.001061

males:  

29–30 . . . . . . . . . . . . 0.001420

30–31 . . . . . . . . . . . . 0.001448

white population

29–30 . . . . . . . . . . . . 0.001005

30–31 . . . . . . . . . . . . 0.001037

white males

29–30 . . . . . . . . . . . . 0.001372

30–31 . . . . . . . . . . . . 0.001399

non hispanic white population

29–30 . . . . . . . . . . . . 0.001083

30–31 . . . . . . . . . . . . 0.001116

non hispanic white males

29–30 . . . . . . . . . . . . 0.001477

30–31 . . . . . . . . . . . . 0.001503

jacob, non hispanic white male. 30 years old.

probability that jacob lives to be 30 years old. 

since the given probabilities are probabilities of dying, i think we simply subtract it from 1 to get the probability of living. we will use the probability of non hispanic white male.

                                          probability of living to be 30 y.o.

29 - 30 : 1 - 0.001477 = 0.998523

30 - 31 : 1 - 0.001503 = 0.998497