The following table shows the time difference between several cities and Beijing (the number with a plus sign indicates the time earlier than Beijing time at the same time) paris-7 Tokyo + 1 new york-14 If Beijing time is 8 p.m., what's Paris time? If it's 8:00 p.m. Beijing time and Xiao Ming is calling his friends in New York, do you think it's appropriate? There should be a formula

The following table shows the time difference between several cities and Beijing (the number with a plus sign indicates the time earlier than Beijing time at the same time) paris-7 Tokyo + 1 new york-14 If Beijing time is 8 p.m., what's Paris time? If it's 8:00 p.m. Beijing time and Xiao Ming is calling his friends in New York, do you think it's appropriate? There should be a formula

Paris: 20-7 = 13:00 p.m
New York: 20-14 = 6 am
Well, I'll change it all for 24 hours
inappropriate

The following table shows the time difference between cities in several countries and Beijing (with the right book represents the time earlier than Beijing). New york-13 paris-7 Tokyo + 1
(1) If it's 8:00 a.m. Beijing time, what's Tokyo time?
(2) If Zhao Zhiqiang calls his sister in New York at 3:00 p.m. Beijing time, do you think it is appropriate?

1. Because Tokyo is + 1, Tokyo time is Beijing time + 1, that is 8 + 1 in the morning = 9 o'clock
2. Because the time difference between New York and Beijing is - 13, Beijing time is 3:00 p.m., that is 15:00 p.m., New York time should be 15-13 = 2, that is, 2:00 a.m. New York time. It's not appropriate to call at this time. This answer is absolutely correct

If the time difference between Tokyo and Beijing is one hour, if Beijing time is 8:00, what time is New York
Is it due to increase or decrease?

Time difference between Beijing and New York
Current Saturday, September 17, 2011 10:12:02 (daylight time)
Current Beijing time 22:13:03, Saturday, September 17, 2011
Note: Beijing time is 8:00 a.m. on September 17; New York time is 20:00 p.m. on September 16

The following table shows the time difference between several foreign cities and Beijing (positive number means the time earlier than Beijing at the same time): New York: - 13, Paris: - 7, Tokyo: - 1
Chicago: 14. If Beijing time is 8:00 a.m., what's New York time and Tokyo time?

New York: 21:00
Tokyo: 7:00
Chicago: 22:00

There are two schemes for mobile phone charging in a telecommunication company. Scheme one and scheme two
Scheme 1: the monthly rent is 30 yuan, and the local call fee is 0.4 yuan / min; scheme 2: no monthly rent, and the local call fee is 0.6 yuan / min. Mr. Chen estimates that the local call time is between 100 minutes and 200 minutes per month. Which scheme is more cost-effective?

In fact, the two programs are not bad, draw an image to know
The plan of two yuan per 10 minutes is more expensive than the plan of one yuan per 10 minutes
Scheme 2 costs 10 yuan more than scheme 1 in 200 minutes

There are two schemes for mobile phone charging in a telecommunication company
There are two mobile phone charging schemes for a telecom company: scheme 1: monthly rent 50 yuan, local call fee 0.40 yuan / min; scheme 2: no monthly rent, local call fee 0.60 yuan / min

According to scheme 1, the monthly cost is 50 + 0.4x
According to scheme 2, the monthly cost is 0.6x
When the cost of scheme 1 is higher than that of scheme 2, there are: 50 + 0.4x > 0.6x
The solution is: X

There are two ways for a telecom company to pay the phone fee: one is to pay the monthly rent of 15 yuan, and charge 0.20 yuan for each minute of a call; the other is not to pay the monthly rent, but charge 0.30 yuan for one minute of a call

1. According to 10 minutes a day, January is 300 minutes
2. The first cost is 15 + 300 * 0.2 = 75 yuan
3. The second cost is 300 * 0.3 = 90 yuan
4. The second one is easy to use

China Mobile has two kinds of mobile phone cards to choose from. The first one is "global link": the monthly landline fee is 50 yuan, and the call fee is 0.4 yuan / min. the second one is "China Travel": no landline fee, and the call fee is 0.6 yuan / min?

If the call time is x, then 50 + 0.4x = 0.6x, x = 250 minutes

In Chapter one, we have considered the following two mobile communication modes:
Method 1 (monthly rent 30 yuan / month, local call fee 0.30 yuan / min) method 2 (monthly rent 0 yuan / min, local call fee 0.40 yuan / min) use the function method to answer which method should be chosen with less cost

30+0.30X=0.40X
x=300
More than 300 in mode 1
Less than 300 with mode 2

What are the characteristics of linear equation with one variable, what is the general form of linear equation with one variable, and what is the solution of linear equation with one variable
Big as long as the answer is what the characteristics of the line, I know the rest

Features: there is only one unknowns, and the formulas containing unknowns are integers, and the number of unknowns is 1
The form is ax + B = 0 (a, B are constants, and a ≠ 0)
The value of the unknown which makes the left and right sides of the equation equal is called the solution of the equation