Estimate the total number of hours required for Americans to do their laundry every year.
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CIsrification:
Is it at home laundry or both at home and laundromats? Both
Is folding and ironing a part of laundry : No
Formulae = ((total population) * (Family, individual split) * (having laundry at home and laundromat split) * (time taken for at home and laundromat))
Total population = 320 Million
Assuming equal split by age 0-80 years
Non families = 100 Million
Family population = 220 Million, # of families = 75 million approx
Non families = % having laundry at home/apartments = 75% = 75 Million, laundromats = 25 million
Families with laundry at home = 90%, 68 Million, 7 million without laundry at home
# of loads is assumed to be 1, certain occasions might be 2 but majority will be 1
# of times laundry - families once a week, non families once in 2 weeks
Time spent doing laundry at home: People put in laundry and change it to drier and go about doing their thing
While at laundromats there might be a waiting period and people might wait as their laundry is getting done
Time for putting clothes in laundry + taking it and putting in drier and taking it out = 3 minutes
Families = 52 * 3 = 156 minutes
Non Families = 26 * 3 = 78 minutes
At home time spent by families = 68 * 156 = 10,000 million approx minutes
At home time spent by non families = 75 * 78 = 6000 million approx minutes
Laundromats one cycle takes washing + drying = 2 hours
Families = 7 Millon * 156 + 25 million * 120 = 7 million * 276 = 2000 million minutes
Non Families = 25 million * 200 minutes = 5000 million minutes
total time spent = 10,000 + 6000 + 2000 + 5000 = 23,000 million minutes = 24 Billion Minutes
Assumption - Not taking into account homeless, and for laundromats they will be there in the laundromat waiting
Is it at home laundry or both at home and laundromats? Both
Is folding and ironing a part of laundry : No
Formulae = ((total population) * (Family, individual split) * (having laundry at home and laundromat split) * (time taken for at home and laundromat))
Total population = 320 Million
Assuming equal split by age 0-80 years
Non families = 100 Million
Family population = 220 Million, # of families = 75 million approx
Non families = % having laundry at home/apartments = 75% = 75 Million, laundromats = 25 million
Families with laundry at home = 90%, 68 Million, 7 million without laundry at home
# of loads is assumed to be 1, certain occasions might be 2 but majority will be 1
# of times laundry - families once a week, non families once in 2 weeks
Time spent doing laundry at home: People put in laundry and change it to drier and go about doing their thing
While at laundromats there might be a waiting period and people might wait as their laundry is getting done
Time for putting clothes in laundry + taking it and putting in drier and taking it out = 3 minutes
Families = 52 * 3 = 156 minutes
Non Families = 26 * 3 = 78 minutes
At home time spent by families = 68 * 156 = 10,000 million approx minutes
At home time spent by non families = 75 * 78 = 6000 million approx minutes
Laundromats one cycle takes washing + drying = 2 hours
Families = 7 Millon * 156 + 25 million * 120 = 7 million * 276 = 2000 million minutes
Non Families = 25 million * 200 minutes = 5000 million minutes
total time spent = 10,000 + 6000 + 2000 + 5000 = 23,000 million minutes = 24 Billion Minutes
Assumption - Not taking into account homeless, and for laundromats they will be there in the laundromat waiting
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Before we get started, I'd like to make sure I'm understanding the question correctly:
- I'm assuming "do their laundry" means doing it at home. Or does that also include dropping off and picking up from Dry cleaning? It includes only home laundry.
- I'm assuming "do their laundry" includes everything related to getting clothes ready for the next use i.e. piling them to prepare for washing, drying, folding, ironing, putting clothes away. Yes, it includes all of those.
- Does it include wait time while the machine washes or dries clothes? Yes.
- I'd assume the year 2019 works for this purpose? Yes.
- Does it include both clothes and bed sheets / towels? Yes.
Ok, let's get started then.
Total number of hours required for Americans to do their laundry every year = Total number of Americans / Avg of people per household * Avg number of laundry loads * Average time per laundry load
For the average household with three people / two baths / two bedrooms:
Type of Laundry Item | Avg Laundry runs per month | Number of loads per run | % dry cleaned | Avg time per laundry load (assuming close to 100% of households use drier) | Total (hrs per month) |
Bed sheets/blankets/pillow cases | 4 | 2 | 10% | 2.25 hours (45mins wash, 45 mins dry, 15 mins fold/change sheets) | ~16 |
Clothes | 4 | 3 | 30% | 2.25 hours (45 min wash, 45 min dry, 45 mins fold/put away) | 11 |
Towels | 6 | 1.5 | 0% | 2 hours (45mins wash, 1 hr dry, 15 mins fold/change sheets) | 18 |
Total | 45 hours per month |
45 hours per month (~2 full days per month) seems high, but this is based on the original assumption that we should count the time machines are running, even if we're doing something else in the meantime.
Total number of hours required for Americans to do their laundry every year = 300 Million people / 3 people per household * 45 hours per month per household * 12 months = 54 Billion hours per year in 2019
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