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A math problem, do not have two unknown equations, to sixth grade pupils to accept the method, by the way, explain, hard you! In order to save resources and protect the environment, a city's Electric Power Bureau has been replacing Gufeng meters for residents for free since January this year, and then stipulates that: from 8:00 to 21:00 every day, 0.80 yuan per kilowatt hour ("peak electricity" price); from 21:00 to 8:00 the next day, 0.55 yuan per kilowatt hour (valley electricity price). At present, residents who do not use Gufeng meters charge 0.75 yuan per kilowatt hour, In March, we paid 91.5 yuan for electricity. After calculation, we can save 6 yuan by using peak valley electricity meter. 1. How many kilowatt hours does the small owner use in March? 2. How many kilowatt hours did the "peak electricity" and "valley electricity" use in March? We can't find it online, so please help us. It's hard to get the answer before 11 o'clock
This is similar to the cage of chickens and rabbits (91.5 + 6) / 0.75 = 130, with a total consumption of 130 kwh. If the peak power is 130 * 0.80 = 104 yuan, the difference between 104 and 91.5 is 104-91.5 = 12.5 yuan, the difference between 0.80 and 0.55 is 0.8-0.55 = 0.25 yuan, and the difference between 12.5 yuan is 12.5 / 0.25 = 50 kwh, the peak power consumption is 130-50 = 80 thousand
Do not use binary linear equation to solve, only one unknown number can be set at most
The prerequisite is shown in the title
1. Squirrels can pick 20 pine nuts on sunny days and 12 on rainy days. Now there are 112 in total. But I know that squirrels pick 14 on average every day. How many days is rainy day?
2. The school bought 5 basketball and 6 volleyball, which cost 194 yuan in total. It is known that basketball is 8 yuan more expensive than volleyball. How much is a basketball?
1. It took a total of 112 / 14 = 8 (days)
If there are x sunny days, there are 8-x cloudy days
20X+12（8－X）＝112
20X+96－12X＝112
8X＝16
X＝2
8-x = 8-2 = 6 (days)
2: If basketball costs X Yuan, volleyball costs (X-8) yuan
5x+6(x-8)=194
The solution is: x = 22
Hope to adopt
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