Question

Dilution		Hand-washing treatment
		10 sec water rinse	30 se soap/water wash	EtOH Sanitizer	Control
100			39
10-1		215	2	254	256
10-2		43		60	187

Dilution		Surface-Cleaning Treatment
		Water Wash	Soap/water wash	EtOH	Windex	Chlorox Wipes	Control
100		480	260	50	20	0
10-1		1360	1200	200	300	100	6900
10-2							TNTC

Determine the countable dilution for each treatment and control (the one that gives between 30 and 300 CFUs on the plate) and calculate CFUs m^-1 glove juice.

Show your work here (be clear, and carry units throughout the calculation)

Answer 1

nothing has been provided in the question like how much ml of the solutiion is plated, whether the colonies are per plate or per tube, what is the total volume, etc.

i assume 1 ml of the dilution are plated and number of colonies per plate is given.

countable dilution  

Hand washing treatment

10 sec water rinse- 10^-1

30 se soap/water rinse- 10^-1

EtOH sanitizer- 10^-1

control- 10^-1

surface cleaning treatment

water wash- 10^-2

soap water/wash- 10^-2

EtOH- 10^-1

windex- 10^-1

chlorox wipes- 10^-1

control- 10^-3