Question

Abraham wanted to do plantation in the backyard of his house. To do it in a more interesting way, he decided to follow a fixed pattern. He divided the whole field in 7 rows. Starting from the last row, he planted 21 plants in the last row and 13 plants in the second last and 8 plants in third row from last. How many plants will he plant in the fourth row from the last?

• A. 3
• B. 6
• C. 5
• D. 2

Answer 1

The correct option is C

5

Abraham is following Fibonacci sequence. Fibonacci sequence is the series of numbers - 0, 1, 1, 2, 3, 5, 8, 13, 21, 34... He is having 7 rows and he started from the number 21 and he is moving in descending order like 21, 13, and 8. So the next will be 5.
Therefore following this pattern he will plant 5 plants in the fourth row from the last.