PSTV is planning to show **wildlife films** in the time slot between 1 o'clock and 5 o'clock on Thursdays.

If each programme lasts **half an hour**, how many **different programmes** will they need to buy to fill the time slot?

This problem helps explore the idea of half-hours. This is both an important concept in time and a useful application of the simple fraction one-half.

### Problem

PSTV is planning to show wildlife films in the time slot between 1 o'clock and 5 o'clock on Thursdays.

If each programme lasts half an hour, how many different programmes will they need to buy to fill the time slot?

#### Teaching Sequence

- Introduce the problem by displaying half past three on the clock and asking what programmes might be on TV at that time.
- Move the hands to 4 o'clock and ask what programmes would now be on.
- Pose the problem.
- Ask the students questions that focus their thinking on telling the time in ½ hours.

*What time is this?*

How do you know?

Tell me what the time would be in half an hour from then?

Can you show me that time on the clock? - Encourage the students to plan ways to keep track of their solution so that they can share it with others.
- Share solutions.

#### Extension to the problem

How many programmes would PSTV need from 11 o'clock in the morning until 6 o'clock in the evening?

#### Solution

This might be done with rods or by using a clock face. It might also be another chance to practice counting in 2s.

There are four hours to fill in. Each hour has two half-hour programmes. So PSTV needs 2 + 2 + 2 + 2 equals 8 programmes.