passwella.
Menu

UI Post-UTME Mathematics 2018 (Model questions) Question 18

Question 18

Progressions

The fourth term of an arithmetic progression (A.P) is 1 less than twice the second term. If the sixth term is 7, find the first term

  1. A.3
  2. B.2
  3. C.4
  4. D.5
Show the answer and explanation

Answer: B (2)

Explanation

a + 3d = 2(a + d) − 1 gives d = a − 1; a + 5d = 7 gives 6a − 5 = 7, so a = 2.