A biologist is interested in the number of cells in a sample of fluid. A small amount of this fluid is taken from the sample and put into a haemocytometer. The configuration details for the haemocytometer grid are given on the right hand side. By counting the cells and scaling up appropriately, work out an estimate for the number of cells in the original sample.
NOTES AND BACKGROUND
The haemocytometer is a device which is used to count the number of cells in a sample of fluid, from which concentrations and other quantities might be calculated. A haemocytometer is made from a small glass chamber crossed with calibrated wires to aid counting. A small sample of the fluid is placed in the chamber and then examined under a microscope.They are commonly used in laboratories.
The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the
NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to
embed rich mathematical tasks into everyday classroom practice.