Question

10th term of arithmetic sequence is 48 common difference is 3 find 3rd term?

Answer 1

Answer:

The 4th term of an arithmetic sequence is 26 and the 10th term is 68. Find the first three term ant the sum of the 10th terms. what would be the answers?

It takes 6 steps to increase by 42 units, 7 units per step → d = 7

a(n) = a1 + 7(n - 1)

a(4) = 26 = a1 + 7*3 → a1 = 26 - 21 = 5

a(n) = 5 + 7(n - 1)

Add 7 to get each successive term: 5, 12, 19

The sum of the sequence is the average of the first and last terms multiplied by the number of terms

a(10) = 5 + 7*9 = 68

s(10) = (5 + 68) / 2 * 10 = 5*73 = 365

Step-by-step explanation: