The rule is to subtract 6
Answer:
Step-by-step explanation:
<u>This is an AP with:</u>
- The first term a₁ = 12
- Common difference d = 3
- Number of terms n = 40
<u>Number of the seats:</u>
- Sₙ = 1/2*n(a₁ + aₙ) = 1/2n(2a₁ + (n - 1)d)
- S₄₀ = 1/2*40(12*2 + 39*3) = 2820 seats
<u>Formula of nth term:</u>
- aₙ = a₁ + (n - 1)d
- aₙ = 12 + (n - 1)*3 = 12 + 3n - 3 = 3n + 9
- aₙ = 3n + 9
1. Let x = #
2. "Five less than six times a number" can be written as: 6x - 5
3. "is at least" is the same as "greater than or equal to" and can be written as: >=
4. "nine subtracted from two times that number" can be written as: 2x - 9
5. the equation is: 6x - 5 >= 2x - 9
6. solve for x by grouping the x variable terms on one side and the constants on the other side:
6x - 5 >= 2x - 9
-2x +5 -2X +5
4x >= -4
7. divide each side by 4, and you get: x = -1
Answer:
504 ways
Step-by-step explanation:
The first position can go in 9 ways
The second position can go to the team in 8 ways
The third position can go to the team in 7 ways
Therefore, the first,second and third position can go to the team in:
9 X 8 X 7=504 ways
or Simply, we can use <u>Permutation</u>.
ways