Respuesta :
In this question you need to find the lowest common multiple. I like to
do it the factor tree way:
15 9
/ \ / \
3 5 3 3
See how there are both a 3 in the 15 factor tree and there is at least on three in the 9 factor tree. So when you find the LCM, you combine the two threes from the different factor trees like this:
3 x 5 x 3 = 45
So every 45 minutes the bus would be at the bus stop together
Now simply add the 45mins onto the 1:25
Answer: 2:10
15 9
/ \ / \
3 5 3 3
See how there are both a 3 in the 15 factor tree and there is at least on three in the 9 factor tree. So when you find the LCM, you combine the two threes from the different factor trees like this:
3 x 5 x 3 = 45
So every 45 minutes the bus would be at the bus stop together
Now simply add the 45mins onto the 1:25
Answer: 2:10
9 = 3^
15 = 3 x 5
both of them have 3, but take the bigger one ( 3^ )
LCM = 3^ x 5 = 45 min
1 : 25 + 0 : 45 = 2 : 10
15 = 3 x 5
both of them have 3, but take the bigger one ( 3^ )
LCM = 3^ x 5 = 45 min
1 : 25 + 0 : 45 = 2 : 10