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[sarojini23]

Hi there,

Can you please help me with this question.

A television company broadcasts programmed for schools on two different channels. Channels One has programmes which each last twenty-five minutes and Channel Two has programmes which each last thirty-five minutes.
What is the next time when both Channels commence their programmes together if they each start broadcasting at 9.15 a.m? You may assume that there are no gaps between programmes.

[KatieB]

Hi there,

Can you please help me with this question.

A television company broadcasts programmed for schools on two different channels. Channels One has programmes which each last twenty-five minutes and Channel Two has programmes which each last thirty-five minutes.
What is the next time when both Channels commence their programmes together if they each start broadcasting at 9.15 a.m? You may assume that there are no gaps between programmes.

Just find the LCM of 25 and 35 by expressing 25 and 35 as a product of there prime factors.

When you have the LCM just add this to 9.15 a.m. to give you the answer.

[sarojini23]

Hi KatieB,

Thank you so much for your help!

The answer is 3.07. Is this correct?

Thanks once again.

[KatieB]

What did you get for the LCM?

[sarojini23]

Hi KatieB,

LCM = 175

Thanks

[KatieB]

Well done. Now just add this number of minutes to 9:15 am to give the next time both broadcast coincide.

9:15 + 175 mins = 12:10

Hope you get that now.

The 25 minute broadcast would have repeated 175/25 = 7 times whilst the 35 minute broadcast would have repeated 175/35 = 5 times

[sarojini23]

Thank You KatieB.

Your help is most appreciated!