number work practice - addition and subtraction, hopefully without a calculator
the powerpoint is here
some tasks involve simple simultaneous equations (e.g. two numbers sum to 10 with a difference of 2, what are they?)
the numbers are the lengths of the squares rather than their area
sometimes you have to find the right lengths to compare e.g. in the 7, 5, 7 resource (two) below,
having found 12 (above the 7 + 5) then 12 + 5 = ? + 7
an 'imperfectly squared' rectangle
what are the missing lengths?