The 21st term of the given arithmetic sequence is 83. The nth term of an arithmetic sequence is applied to find the required value where n = 21.
<h3>What is the nth term of an arithmetic series?</h3>
The nth term of an arithmetic sequence is calculated by the formula
aₙ = a + (n - 1) · d
Here the first term is 'a' and the common difference is 'd'.
<h3>Calculation:</h3>
The given sequence is an arithmetic sequence.
3, 7, 11, 15, 19, ....
So, the first term in the sequence is a = 3 and the common difference between the terms of the given sequence is d = 7 - 3 = 4.
Thus, the required 21st term in the sequence is
a₂₁ = 3 + (21 - 1) × 4
⇒ a₂₁ = 3 + 20 × 4
⇒ a₂₁ = 3 + 80
∴ a₂₁ = 83
So, the 21st term in the given arithmetic sequence is 83.
Learn more about the arithmetic sequence here:
brainly.com/question/6561461
#SPJ1
Answer:
A
Step-by-step explanation:
The linear model can be assessed by the checking the independent variables having power 1 which shows the linear relationship between x and y. For example, as in the option B, C and D, the power of Xi's is one. Whereas the non linear model has the power for independent variables greater than 1. For example, as in option A the model is a quadratic model because X associated with β2 has a power of a 2.
Thus the nonlinear model can be expressed as
Y = β0 + β1X + (β2X)2 + ε.
I’m not entirely sure what the question is asking because of the first word but the second equation (y=-x + 3) satisfies the conditions.
Answer:
60 m/h
Step-by-step explanation:
1. the basic formula is Time=Distance/Speed;
2. total time is time1 (for 84 miles)+time2 (for 130 miles)=time (4 hours);
3. the time for the first 84 mi. is time1=84/S;
4. the time for the rest 130 mi. is time2=130/(S-10);
5. using all the data of items 2-4, it is possible to substitute into the basic formula and resolve an equation:


note, that the value of speed has one condition: s>10. It means, the only value is true: 60 miles per hour.
5/10=0.5x7=3.5. the width of the photograph is 3.5inch