Answer:
1. Cooking time saved in a month = 42.86 * 3/4 = 32 hours
2. Cooking time saved in a year = 520 * 3/4 = 390 hours
3. Since the household saves 390 hours in a year using pressure cooker, it will then save 390 * $2 = $780
Step-by-step explanation:
Hours spent cooking on average per week = 10 hours
Hours spend cooking on average per day = 1.43 (10/7), assuming 7 days in a week
Total hours spent on average per month = 42.86 (30 * 10/7), assuming 30 days in a month
Total hours spent on average per year = 520 (52 * 10) hours, assuming 52 weeks in a year.
Savings in time = 3/4
Therefore, the cooking time saved in a month = 42.86 * 3/4 = 32 hours
And the cooking time saved in a year = 520 * 3/4 = 390 hours
If on the average, a household spends $20 in natural gas for cooking per month, the money it would save by using a pressure cooker in a year will be equal to:
Cost of each hour of cooking without pressure cooker = $20/10 = $2 per hour
Since the household saves 390 hours in a year using pressure cooker, it will then save
= Hours saved multiplied by hourly cost of gas
= 390 * $2
= $780
