Question

Kate recently read an article referring to environment pollution and thought of planting a couple of trees with the help of her friends. She wants to plant 15 oak trees, 27 pine trees and 9 teak trees but in equal number of rows that is each row will have 1 type of tree and all the trees will be planted in equal number of rows. What will be the maximum number of trees in 1 row and determine the total number of rows needed to plant all the trees?

• A. 3, 17
• B. 3, 15
• C. 9, 17
• D. 4,15

Answer 1

The correct option is A 3, 17

As we know that we have to plant the tress in equal number of rows and 1 row can have only 1 type of tree. Then it means that we have to find the HCF of the numbers 15, 27 , 9. Once we get the HCF of the numbers, we will know the number of trees to be planted in 1 row.
The HCF of 15,27, and 9 is 3. So each row will have 3 trees of 1 kind. Now to know the total number of rows required to accommodate all the trees, we have to find the number of rows required by each kind of trees. Oak trees will need (15 divided by 3) 5 rows, pine trees will need ( 27 divided by 3) 9 rows and lastly teak trees will need (9 divided 3) 3 rows. So the total number of rows required will be 17 rows.

This is the division method for finding the HCF. The last divisor which gives the remainder as 0 is the required HCF.