1. The opposite number of a positive number is less than the opposite number of its reciprocal. On the number axis, where is the corresponding point of this number? 2. Calculation: 1-2+3-4+.+2003-2004+2005=?

1. Let this positive number be X
The opposite number of X is - X
The reciprocal of X is 1 / X (where x is obviously positive,
The inverse of the reciprocal of X is - 1 / X
-x〈 -1/x
X 〉 1 / X (multiply both sides by - 1, sign opposite)
X2 〉 1 (x is a positive number, and the multiplication of both sides does not change the sign)
X ＞ 1 or X ＜ - 1
You should know the position on the number axis
2. In fact, you can see it at a glance by adding brackets
（1-2）+（3-4）+（5-6）+…… +（2003-2004）+2005
= （-1）+（-1）+（-1）+…… +（-1）+2005
=（-1）×1002+2005=2005-1002=1003
About how many - 1s there are, a total of 1 to 2004, a total of 2004 numbers are subtracted by two, so they are divided into 1002 pairs
Very detailed, hope to understand

The first question 8, 5, 2 and 7 count for 24 points
The second question 11,11,1,5 is 24 points
The third question 1, 4, 5 and 6 count 24 points
See your age to 3, and then multiply by 2, and then add your age, I will know your age, to which the Yunhan mathematical theory
1、 Two, three, four, five, six, seven and eight are all the beginning. Fill in the four character idiom and say other idioms with numbers

In the process of flood relief, a military rescue team resettled the victims and allocated several dormitories. If there were 8 people in each dorm, there would be 12 beds less. If there were 9 people in each dorm, there would be 2 dormitories vacant. Q: how many people were resettled this time?

There are x dormitories,
8x+12=9(x-2)
That is, 8x + 12 = 9x-18
The solution is x = 30
Number of people: 8 * 30 + 12 = 252
A: 252 people have been resettled this time

The purchase price of a suit in a store is 300 yuan. If the price of the suit is 80% of the price, the profit will be 100 yuan. If the price of the suit is x yuan, the equation can be listed as follows______ ．

Suppose the price of the garment is x yuan, then the actual price is 80% X. according to the equation of equivalent series, 80% x-300 = 100

The purchase price of a suit in a store is 300 yuan. If the price of the suit is 80% of the price, the profit will be 100 yuan. If the price of the suit is x yuan, the equation can be listed as follows______ ．

Suppose the price of the garment is x yuan, then the actual price is 80% X. according to the equation of equivalent series, 80% x-300 = 100

A garment with a purchase price of 200 yuan can still make a profit of 10% if it is sold at a 20% discount on the price______ Yuan

Suppose the price of the dress is x yuan. X × 80% = 200 × (1 + 10%), the solution is x = 275, so the answer is 275

The purchase price of a suit in a store is 300 yuan. If 80% of the price can make a profit of 100 yuan, how much is the price of the suit?

If the price of clothing is x, the calculation method is as follows:
300+100=80%X
X=500
A: the price of the dress is 500 yuan

A garment with a purchase price of 200 yuan can still make a profit of 10% if it is sold at a 20% discount on the price______ Yuan

Suppose the price of the dress is x yuan. X × 80% = 200 × (1 + 10%), the solution is x = 275, so the answer is 275

A store sells clothes at the price of 100 yuan per piece, making a profit of 20%. What's the purchase price?
The formula of the equation!

100 times one percent minus 20 percent is 100 times 80 percent, which is 80 yuan

The price of a piece of clothing is 100 yuan. If it is sold at a 60% discount on the price, it will still make a profit of 20 yuan. How much is the price of the clothing

If the price of the clothes is x yuan, then:
0.6x-20=100
The solution is x = 200
A: the price of clothes is 200 yuan

1. The opposite number of a positive number is less than the opposite number of its reciprocal. On the number axis, where is the corresponding point of this number? 2. Calculation: 1-2+3-4+.+2003-2004+2005=?