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### Number and algebra

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### For younger learners

### Advanced mathematics

# How Many Days?

### Why do this
problem?

### Possible approach

### Key questions

### Possible extension

### Possible support

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### Planet Plex Time

### On What Day Did it Happen?

### Calendars

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Links to the NRICH website Home page

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Age 5 to 7

Challenge Level

- Problem
- Getting Started
- Student Solutions
- Teachers' Resources

For young children
this problem is not as trivial as it first sounds. The
difficulty in visualising or reciting the names of the months in
order and how many days there are in each will probably lead to
some sort of recording or need to look at a calendar or diary. At
some point the discussion will involve deciding just what is meant
by 'between'.

It would be helpful if this coincided with work on sequencing
the months of the year and learning the number of days in each
month. Encourage children to discuss the question first in small
groups and decide on what they think the answer might be. Then
allow them to examine a Year 2000 calendar or a diary. Should they
count the starting day and finishing day? Does knowing the starting
day is a Friday and the finishing day is a Saturday help work out
the answer? There is also the fact that February 2000, being a leap
year, has 29 days, to discuss.

What does 'between' mean?

Should we count the starting and finishing days? Why?

Once interpretations have been agreed upon, ask the children
to pose their own similar questions for others to answer. What if
the year was the current year? Could we work out the answer without
going back to the beginning?

Large calendar pages that can be written on may be helpful.
And discussion is always important!

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