Answer:
67
Step-by-step explanation:
From the question given above, the following data were obtained:
Number of terms (n) = 12
Last term (L) = 100
Common difference (d) = 3
First term (a) =?
We can obtain the first term of the arithmetic sequence as follow:
L = a + (n – 1)d
100 = a + (12 – 1)3
100 = a + (11)3
100 = a + 33
Collect like terms
100 – 33 = a
a = 67
Therefore, the first term of the arithmetic sequence is 67
