9514 1404 393
Answer:
63
Step-by-step explanation:
The number of seats in a row will give an arithmetic sequence:
6, 9, 12, 15, ...
The first term is 6; the common difference is 3. The general term is ...
an = a1 +d(n -1) . . . . . . n-th term of sequence with first term a1, difference d
The 20th term of the sequence is ...
a20 = 6 +3(20 -1) = 6 +57 = 63
There would be 63 seats on the 20th row.
4x-24 will be your correct awnser
If you would like to calculate the arithmetic mean, geometric mean, and harmonic mean from the following averages, you can calculate this using the following steps:
averages: 56.4, 59.8, 55.8
the number of values: 3
arithmetic mean:
(56.4 + 59.8 + 55.8) / 3 = 57.33
geometric mean:
(56.4 * 59.8 * 55.8)^(1/3) = 57.31
harmonic mean:
3 / (1/56.4 + 1/59.8 + 1/55.8) = 57.28
The 4th term is 135
n-1
you get it by using the formula Tn= ar <span />
Answer:
4 brothers and 3 sisters
Step-by-step explanation:
Let x be the number of brothers and y be the number of sisters in the family.
1. Each brother has x-1 brothers and y sisters. If each brother has as many sisters as brothers, then

2. Each sister has y-1 sisters and x brothers. If each sister has twice as many brothers as she has sisters, then

3. Solve the system of two equations:

Then
