# Try this: Predicting reaction time

You will need

• Copy of the graph above
• Ruler
• Pen

Use a line of best fit to make predictions about hand reaction time

• Place a ruler on the graph so it covers all the dots – make sure the ruler has the same downward slope as the data.
• Now, turn the ruler on its side (thin edge of the ruler on the page).
• Keeping the slope the same, move the ruler so that approximately half of the data points appear above the edge of the ruler and half are below it.
• Now, draw a line along the edge of the ruler. This is a line of best fit! Continue reading Try this: Predicting reaction time

# Try this: Soma cube

Safety: This activity uses hot glue. Younger mathematicians should ask an adult to help.

#### You will need

• 27 small cubes – cheap dice are good
• Hot melt glue

#### Making the puzzle

1. This puzzle consists of seven pieces arranged to form one large cube. Each piece is made of three or four smaller cubes glued to form shapes. Click here to download a diagram showing all the pieces you will need to make.
2. Clean your cubes with detergent and dry them thoroughly – this will make the glue stick better. Continue reading Try this: Soma cube

# Try this: Faking random

You will need

• Pen
• Paper
• A die, or two dice

What to do

1. Draw up a grid five squares wide and five squares tall. If you don’t want to draw them, you can download a sheet here. (Six grids per page.)
2. Imagine this grid is a paved area, and it’s just starting to rain. Draw where the first nine raindrops might fall, trying to be as random as possible.
3. Take some time to look at how the rain fell on your paving. Do you think it looks random?
4. Consider the following two questions:
• Did more than one of your drops fall into any of the squares?
• We can see that 16 out of the 25 squares are on the outer edge of the paved area. This is more than half. From your nine drops how many fell on the outside squares?
5. Now repeat the activity, but use rolls of a die to work out where the drops fall. Roll for the row and then the column. Re-roll any 6s (because there are only five columns and rows)
6. How does this new pavement compare to the first one? Which one is more random? Continue reading Try this: Faking random