a) The perimeter of a small rectangle is 20.8cm because if the I shape were to be filled in to make a rectangle, two smaller rectangles would go on either side, meaning that the length of the smaller rectangle is 3 times the height. If you divide the length on the side that 13 is the measurement, divide the 13 by 5 because there are 2 heights and one length. 1 length is three times the height so there are 5 heights in total. 2.6 was our answer so 3 times 2.6 is 7.8. 7.8 is the length and 2.6 is the height. Add 2.6 and 7.8 together, the times by 2, and there's your answer, 20.8cm.
b)The perimeter of the small rectangle is 16cm because no matter how much you move the rectangles around its still going to be the same area. So there are 5 smaller rectangles in the large rectangle so the area of the smaller rectangles is 60 divided by 5 which is 12. The edges had to be multiples of twelve but also 3 times the height had to equal the length so that only left 2 and 6 as possibilities so 2+2+6+6 is your answer, 16cm.
c)The perimeter of the small rectangle is 46cm because no matter how much you move the rectangles around its still going to be the same area. So there are 6 smaller rectangles in the large rectangle so the area of one of the smaller rectangles is 600 divided by 6 which is 100. The edges had to be multiples of 100 but also 3 times the height had to equal the length so after a lot of trial and error we got 17.3 and 5.7 so 17.3+17.3+5.7+5.7 is your answer, 46cm.
d)The perimeter of the small rectangle is 18cm because there are 9 smaller squares in the large rectangle so the area of one of the smaller rectangles is 180 divided by 9 which is 20. The edges had to be multiples of 20 also we noticed that if the small shape was divided into fifths on the long side it all adds up. We got the edges at 5 and 4 so 5+5+4+4= your answer, 18cm.
Yellow Shape Perimeter:
We couldn't get to an answer :(