Make a cube out of straws and have a go at this practical
Reasoning about the number of matches needed to build squares that
share their sides.
How can the same pieces of the tangram make this bowl before and after it was chipped? Use the interactivity to try and work out what is going on!
Many of you sent in correct answers to this
problem, but not all were as well explained as these. Wilson from
Beecroft Primary School wrote to say:
To work out the whether the dice are right- or left-handed, I
pictured the dice in my head and then I matched them up with the
Philip from Woodfall Junior School also took
this approach and says:
You can mentally rotate each die (finding the
missing numbers by using the knowledge that opposite faces add up
to seven) so that this happens, and then you can see if the die is
right-handed, with the two at the front, or left-handed, with the
three at the front.
April from Springfield Junior School explains
exactly what she visualised:
1. Right-handed die
Roll it backwards so the $5$ is at the back and the $1$ is on the
top. The front face will be $2$ because $5+2=7$. $3$ will still be
on the right.
2. Right-handed die
Roll it to the right so the $6$ is on the bottom. That means $1$ is
on the top because $6+1=7$. $3$ is on the right and $2$ stays at
3. Right-handed die
Roll it backwards $2$ times so the $5$ is at the back and the 6 is
on the bottom. The top is $1$ because $6+1=7$, and the front is $2$
because $5+2=7$. $3$ stays on the right.
4. Left-handed die
Roll it forwards so the $6$ is on the bottom. The top is $1$
because $6+1=7$. The $5$ moves from the top to the front. Turn it
left so the five moves to the left hand side and the $3$ moves to
the front. The right hand side is $2$ because $5+2=7$.
This is a great step-by-step way of
approaching the problem, April. Well done.