Question

a city bus arrive at a certain bus stop every 12 minutes well another bus arrives at the same stop every 15 minutes if both buses arrived at 4 p.m. at what time will they next simultaneously arrive again at the bus stop use the ladder method to find either the HCF or lcm and justify your answer

Answer 1

Hi,

5 p.m.

Explanation:

HCF(12,15)=?
LCM(12,15)=?

Ladder method:

`\begin{array}c&15&12\\3&5&4\\\end {array}\\\\\\HCF(15,12)=3\\LCM(15,12)=3*5*4=60\\`

Bus arrived at the same stop every hour (60 min).

1 hour after 4 p.m. is 5 p.m.