Question

When you go to an ophthalmologist for getting your eyes checked, you are asked to identify letters on a board kept at a fixed distance. Make a similar board using a cardboard or thermocol with letters replicating the original board. Test the eyesight of your friends, classmates, parents, teachers, neighbours and grandparents. Make a data table containing figures of the number of people with normal eye sight and defective eye sight.

Answer 1

Testing someone:

1. The person stands 6 metres away from the board.
2. They cover one eye and read the rows from the top down.
3. Note the last row they can read correctly, then repeat for the other eye.
4. Reading the row with the red line (6/6) means normal eyesight.
5. Stopping at a row above it (6/9, 6/12 and so on) means defective eyesight, so that person should see an ophthalmologist.

Data table: The figures below are only an example. Replace them with the results of your own test.

Group tested	Total people	Normal eyesight (6/6)	Defective eyesight	Common defect
Friends/classmates	20	15	5	Myopia
Parents	6	3	3	Myopia/presbyopia
Teachers	8	5	3	Presbyopia
Neighbours	10	6	4	Hypermetropia
Grandparents	4	0	4	Presbyopia/cataract
Total	48	29	19