MATHEMATICS

JAMB 2022 - Question 4

Mathematics 2022 JAMB Past Questions - Question 4: The sum of the first five terms 0f the series 4+2+1… is

The sum of the first five terms 0f the series 4+2+1… is
A:
B:
C:
D:
Examkits App

Examkit's JAMB CBT App

Practice JAMB offline with our Online, PC and Mobile App

  • ✅ 25+ years of past questions (2000 to 2025)
  • ✅ Video solutions and explanation to questions
  • ✅ E-library
  • ✅ Study by topic
  • ✅ And more.

Correct Answer

D

Explanation

To find the sum of the first five terms of the series 4 + 2 + 1 + ..., we need to determine the pattern or formula for the series. From the given terms, we can observe that each term is half of the previous term. The first term is 4, the second term is half of 4 (2), the third term is half of 2 (1), and so on. Using this pattern, we can write the general formula for the nth term of the series as:aₙ = 4 * (1/2)^(n-1)To find the sum of the first five terms, we can substitute the values of n from 1 to 5 into the formula and add them up:S₅ = a₁ + a₂ + a₃ + a₄ + a₅    = 4 * (1/2)^(1-1) + 4 * (1/2)^(2-1) + 4 * (1/2)^(3-1) + 4 * (1/2)^(4-1) + 4 * (1/2)^(5-1)    = 4 * 1 + 4 * (1/2) + 4 * (1/4) + 4 * (1/8) + 4 * (1/16)    = 4 + 2 + 1 + 1/2 + 1/4    = 8.75Therefore, the sum of the first five terms of the series 4 + 2 + 1 + ... is 8.75.

Frequently Asked Questions

Examkits is a JAMB CBT practice platform that provides over 20 years of past questions, Post UTME questions, and detailed video solutions to help students prepare for their exams.

You can practice JAMB past questions online, on Android, or on a desktop using the Examkits app. Just register on our website and choose your preferred device.

Yes. Our Android and Windows versions support offline usage. Once downloaded and activated, no internet is required to use most of the features.

Yes, Examkits provides detailed video explanations for all JAMB past questions from 2000 to 2024, helping students understand how to solve each problem.

Examkits offers free practice for some subjects. However, full access requires a one-time affordable activation fee for each version of the app.