Question

Three babies A, B and C cry out at every interval of

time. Baby A cries out at every 20 minutes, while B
cries out at every 30 minutes and C at every 40
minutes. If they are observed at the same time, after
what time will the three of them cry together?​

Answer 1

the answer is below :)

Explanation:

for this we have to use lcm of 20 30 and 40

2|20,30,40

2|10,15,20

2|5,15,10

5|1,3,2

2|1,3,1

3|,1,1

120÷60

after 2 hours

Answer 2

LCM of 20, 30, and 40

LCM = 120

they would cry together for the first time in 120 minutes.