Final answer:
To find the percentage of people who used neither Colgate toothpaste nor Everest toothpaste, subtract the number of people who used both from the total number of people and divide by the total number. Therefore, 36% of the people in the village used neither Colgate toothpaste nor Everest toothpaste.
Step-by-step explanation:
To find the percentage of people who used neither Colgate toothpaste nor Everest toothpaste, we need to subtract the number of people who used both from the total number of people in the village. We can then divide this number by the total number of people and multiply by 100 to express the answer as a percentage.
Total number of people in the village = 5000
Number of people who used both toothpastes = 100
Number of people who used neither toothpaste = Total number of people - Number of people who used Colgate - Number of people who used Everest + Number of people who used both
= 5000 - 2800 - 500 + 100 = 1800
Percentage of people who used neither Colgate toothpaste nor Everest toothpaste = (Number of people who used neither toothpaste / Total number of people) x 100
= (1800 / 5000) x 100 = 36%