How many different rectangles can be made with 10sq cm perimeter?

Answer 1

An infinite number of them.

Here are a few:

0.1 x 4.9

0.2 x 4.8

0.3 x 4.7

0.4 x 4.6

0.5 x 4.5

0.9 x 4.1

1 x 4

1.5 x 3.5

2 x 3

2.4 x 2.6

2.41 x 2.59

2.42 x 2.58

2.43 x 2.57

2.4300001 x 2.5699999

2.4300002 x 2.5699998

2.4300003 x 2.5699997

.

.

etc.