Answer:
aₙ = 7n +29
Step-by-step explanation:
22 ; 15 ; 8; 1;........aₙ
aₙ = -7n +29
Answer: aₙ = -12 + 4*n
Step-by-step explanation:
We know that:
a₃ = 0
a₄ = 4
a₅ = 8
a₆ = 12
a₇ = 16
This seems to be an arithmetic sequence.
To test this, we need to calculate the difference between any two consecutive terms in the sequence, and this must be a constant for any pair that we choose.
a₄ - a₃ = 4 - 0 = 4
a₅ - a₄ = 8 - 4 = 4
a₆ - a₅ = 12 - 8 = 4
etc
we can conclude that this is an arithmetic sequence.
The n-th term in an arithmetic sequence, where the increase between consecutive terms is 4, is:
aₙ = aₙ₋₁ + 4.
Another way is:
aₙ = a₀ + n*4.
Where to find a₀, we can start with the value that we know and go back:
a₂ = a₃ - 4 = -4
a₁ = a₂ - 4 = -8
a₀ = a₁ - 4 = -12
Then the n-th term can be written as:
aₙ = -12 + 4*n
Answer:
rewrite what as the unit rate?
Step-by-step explanation:
What is the question
Based on the given parameters of a = 1.7 cubic feet and concrete for first 4 steps as 17 cubic feet, the concrete is required for the first 12 steps is 132.6 cubic feet
<h3>Arithmetic progression</h3>
- First term, a = 1.7 cubic feet
- Sum of first four terms = 17 cubic feet
Sn = n/2 {2a + (n - 1) d}
17 = 4/2{2×1.7 + (4 - 1)d}
17 = 2{3.4 + (3)d}
17 = 2(3.4 + 3d)
17 = 6.8 + 6d
17 - 6.8 = 6d
10.2 = 6d
d = 10.2/6
- Common difference, d = 1.7
Concrete required for first 12 steps;
Sn = n/2 {2a + (n - 1) d}
= 12/2{2×1.7 + (12-1)1.7}
= 6{3.4 + (11) 1.7}
= 6(3.4 + 18.7)
= 6(22.1)
= 132.6
Concrete required for first 12 steps = 132.6 cubic feet
Learn more about sum of arithmetic progression:
brainly.com/question/24205483
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