seats are arranged 15 rows in an auditorium. each row has 10 seats more than the back the last has 50 seats find out the total number of seats
This makes no sense.
If the 15th row has 50 seats,
the 14th row has 40 seats
the 13th row has 30 seats
...
the 10th row has 0 seats
the 9th row has -10 seats ????????
check your question
Btw, there are many "Similar Questions" listed below this, check them out,
they match your problem once you fixed it.
If you meant 50 rows, then since
a = 15
d=10
then
S50 = 50/2 (2*15 + 49*10) = ____ seats total
To find the total number of seats in the auditorium, we need to calculate the sum of the seats in each row.
Given:
Number of rows = 15
Number of seats in the last row, which is the back row = 50
Since each row has 10 seats more than the previous row, we can set up an equation to calculate the number of seats in each row:
Number of seats in a row = Number of seats in the back row + (Number of rows - 1) * 10
Number of seats in each row = 50 + (15 - 1) * 10
= 50 + 14 * 10
= 50 + 140
= 190
Now, to find the total number of seats, we need to multiply the number of seats in each row by the number of rows:
Total number of seats = Number of rows * Number of seats in each row
= 15 * 190
= 2850
Therefore, the total number of seats in the auditorium is 2850.