To determine the common difference and the first term, we need the formula for the nth term of an arithmetic sequence. The formula is:
An = A1 + (n-1)d,
where An represents the nth term, A1 represents the first term, and d represents the common difference.
Given that the second term is a mixed fraction 6 1/2, we can write it as a proper fraction:
Second term = 6 1/2 = 13/2.
Similarly, the tenth term is a mixed fraction 18 1/2:
Tenth term = 18 1/2 = 37/2.
Using the formula, we have:
An = A1 + (n-1)d
37/2 = A1 + (10-1)d
37/2 = A1 + 9d ---(1)
Also, we know that:
An = A1 + (n-1)d
13/2 = A1 + (2-1)d
13/2 = A1 + d ---(2)
Now we have a system of equations (1) and (2) to solve for the common difference and the first term.
To solve the system, we can subtract equation (2) from equation (1):
37/2 - 13/2 = A1 + 9d - (A1 + d)
24/2 = A1 + 9d - A1 - d
12 = 8d
Dividing both sides of the equation by 8:
d = 12/8
Simplifying,
d = 3/2
Now that we have found the common difference, we can substitute it back into equation (2) to solve for the first term:
13/2 = A1 + (3/2)
Subtracting (3/2) from both sides:
13/2 - 3/2 = A1
10/2 = A1
5 = A1
Therefore, the common difference is 3/2 and the first term is 5.
second term= mixed fraction 6 1/2 and Tenth term= mixed fraction 18 1/2, determine the common difference and the first term.
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