Porcelain Primer

Difficulty:
intermediate
Rating:
4-stars
GCSE Marks:
4-marks

GCSE Text:
A patio consists of 92 porcelain tiles, each one measuring 600mm x 600mm. Each tile needs to have a primer painted to the underside before getting placed onto the cement bed.

The primer is supplied in tubs, each tub containing 2 packets of dry power and each packet covering 8m² when mixed with water.

How many tubs of primer are needed to complete the patio?

Suggestions:
This is a good question to test students’ understanding of area, particularly with mixed units. Students normally take 3-4 minutes to answer. The extension task works well for higher paper GCSE students too.

Teachers could extend the learning by considering:

  • The tiles are 18mm thick and are supplied in packs of 2. Each pack weighs 25kg. What is the density of the porcelain? Give your answer in g/cm³.

Time Lapse Videos

Difficulty:
intermediate
Rating:
4-stars
GCSE Marks:
3-marks

GCSE Text:
Charlie’s video camera normally records smooth video at a rate of 25 frames per second.

Today though, Charlie is using it in time lapse mode, where one frame is captured every 15 seconds instead. He records in time lapse mode for 2 hours continually.

a) When the time lapse recording is played back at 25 frames per second, how long will the clip last (in seconds)?

b) The camera has the option to play back at a faster 30 frames per second rate. How much shorter will the clip last if it is played back at this faster rate?

Suggestions:
This is a good question to test students’ understanding of worded questions. Normally words like ‘per’ need to be highlighted, and this is easily a non-calculator arithmetic question. Students take 1-2 minutes to answer this question in full.

Teachers could extend the learning by considering:

  • The normal frame resolution is 1280 x 720 pixels, but has a full HD option of 1920 x 1080.   How many more pixels are there in a full HD frame than the normal frame?