Today we are going to be completing an investigation linked to time. This will be using your knowledge of 24 hour clocks. Read the task below.

Think about the following questions to get you started.

When does 5 appear in the minutes display?

When does 5 appear in the hours display?

How will you know that you have got all the different times?

You can solve this on paper and email your work to Y4upload@broadheath.coventry.sch.uk

The 5 shows in the minute 7 times in 24 hours for example ( 12:05 12:15 12:25 12:35 12:45 12:55 do 24×7= 168.

It would be different because it would be halfedso it’s 12× 7= 84 or you could half 168 to get your answer.

I have done it in my hw

1)12 hour clock:

1)The number 5 appears twice in a 12 hour clock on the hour display.This is at 5am and 5pm.However in the minute display 5 appears many times e.g 2:58,6:45,3:15,12:25,4:56 etc.

2)24 hour clock:

In the hour display 5 appears at 5:00am and 15:00pm.

3)In the minute display 5 appears many times. e.g 00:05,14:55,16:35,2:15,17:45,18:45.

The 5 appears in the minute’s display at 00.05 and 00.55 for every hour

The 5 appears in the morning 05.00 am and later but this shows as 17.00 or 05.00 pm

By checking every hour on the clock

Have a look at the questions again Rajbir. How many times does the 5 appear in the minutes and hours display? For example: 12:05, 12:15.

5 in an hour 5 appears 7 times for example 12:05,12:15,12:25,12:35,12:45,12:50,12:55 so in 12 hour clock 5 will appear 7×12=84 times and in 24 hour time 5 will appear 7×24=168 times that is how I understood

Good Iqra, how will you know that you have got all the different times?

1. 5 will appear 5 past each hour of the day .

2.In the hour display 5 will appear 6 times .

For example;

7.05

7.15

7.25

2.35

7.45

7.55

3.You know the difference because am and pm are different.

Alina, this seems to be the exact same as Bolu’s? Try to do your own work please.

I have completed this task and will email it to you

Super Adeena!

1. 5 appears in every number in the 5 times tables(except the ones in the 10 times tables). So in the minutes display,5 is show 12 times. So in a day 5 appears 288 times in a minutes display.

2. In an hour display it is shown twice. It is shown when it is 5 and 15 o’clock.

3. After each hour,the current number( o’clock) changes.

Good Hamaad, there are lots of interpretations of this question…

How many times does 5 appear in the minutes here:

05, 15, 25, 35, 45, 50, 55, 56, 57, 58, 59. This happens ever hour for 24 hours. so how many is this in total?

1] In minutes in 24hrs on digital clock there would be 192 5s because there are two 5s in 1:55 and an extra in 1:50

Carrying on with 1:05, 1:15, 1:25, 1:35, 1:45, 1:50 and 1:55 = eight 5s

2] In hours on a digital clock there would be two 5s (5:00 and 15:00).

Great Zaid, how will you know that you have got all the different times?

I think you are the closest here Zaid! there are lots of interpretations of this question…

How many times does 5 appear in the minutes here:

05, 15, 25, 35, 45, 55, 56, 57, 58, 59. This happens ever hour for 24 hours. so how many is this in total?

114 5 s in 24 hours

114 in the minutes

2 in the hours

Good try Safya- can you explain how you got to the total 114 in 24 hours?

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12 hours clock

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5 appears 6 times (05,15,25,35,45,55) in an hour in minutes part.

so in 12 hours digit ‘5’ will appear for 12*6 = 72 times + 1 times in hours section (05) so total 73 times.

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24 hours clock

******************

5 appears 6 times (05,15,25,35,45,55) in an hour in minutes part.

so in 24 hours digit ‘5’ will appear for 24*6 = 144 times + 2 times in hours (05, 15) section so total 146 times.

Great Archi! If I was super picky- and said that you could count 55 as two appearances, how would this change your answer?

1. 5 will appear 5 past each hour of the day .

2.In the hour display 5 will appear 6 times .

For example;

7.05

7.15

7.25

2.35

7.45

7.55

3.You know the difference because am and pm are different.

You mean in the minutes display. Good Bolu- you are part way there! Remember 7:55 would be counted as two times as there are two fives. How many times will a 5 appear in the hours display?

I don’t understand the three quetions

Well done for being honest Abdirahman. You need to count how many times you can see the digit 5 on the 24 hour clock.

For example, each hour we see 5 like this:

12:05, 12:15, 12:25. 12:35, 12:45, 12:50, 12:55 = 7 fives per hour.

To figure out how many in the day complete: 7 x 24 = ___

How many times will 5 appear in the hours side? Write out the times to help you. Add this to the total.

1. 5 appears in the minutes display by 7.05 minutes

2. 5 appeares in the minutes display by 17.00 minutes

3.you will know that you’ve got the different times by midnight

Okay Mikolaj, how many times does the digit 5 appear in total from 12am to 12pm?

It appears 2 times.

In 1hour 5 appears 6 times. So in 24hrs it appears 6×24=144 times.

Yes it’s the same for the 12hour clock for the whole day.

1) It appears 144 times in the minutes display. (5,15,25,35,45,55 in every hour)

2) It will appears twice. Once in the morning at 5 o’clock and in the afternoon at 3 o’clock which will be displayed at 15 o’clock.

,3) Because the 1st 12hours are displayed in am and the pm hours are displayed as a 24hour display.

Very well explained Yahya!