It costs 1080 yuan to buy 18 sets of desks and chairs. It is known that the price of one desk and three chairs is equal. How much is each desk? How much is each chair?

Chair = 1080 ／ 18 ／ (1 + 3) = 15 yuan
Table = 15 × 3 = 45 yuan

The school bought 15 sets of desks and chairs, which cost 1800 yuan in total. The price of each desk is just three times that of each chair. How much is the price of each desk and chair
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The school bought 15 sets of desks and chairs, which cost 1800 yuan. The price of each desk is just three times that of each chair
How much is each chair? 2 with 1

Hello, max62118
There are 15 sets of chairs in total
15 × 2 = 30 (sheet)
Each chair:
1800 (15 × 3 + 30) = 24 (yuan)
Each table:
24 × 3 = 72 yuan

A and B two shopping malls sell the same clothes. A sells five more clothes than B. after all the clothes are sold, they all earn 400 yuan. For example, a earns 500 yuan according to the unit price of B. the original unit price of a's clothes is more
Please don't use the equation, because I haven't learned it yet. Please write the process and formula clearly,

Because all of them earn 400 yuan after selling. For example, a earns 500 yuan by selling at the unit price of B, so a earns 100 yuan more by selling clothes at the price of B. because a has five more pieces than B, the total price of these five pieces is 100 yuan. Divide 100 yuan by 5 to get the unit price of each piece, which is 20 yuan. Then bring 20 yuan into the inspection
Formula: (500-400) △ 5 = 20

Find the rule: 3,5,14,55274, (), 11500
What is the law of it?

3*2-1=5
5*3-1=14
14*4-1=55
55*5-1=274
274*6-1=1643
1643*7-1=11500
one thousand six hundred and forty-three

Fill in the number according to the rule: 3,5,14,55274, (?), 11500

Fill in the number according to the rule: 3,5,14,55274, (1643), 11500
3*2-1=5
5*3-1=14
14*4-1=55
55*5-1=274
274*6-1=1643 .

What is the number arrangement rule of 1.5.13.25?

Square of (n-1) + square of n
1=0^+1^ 5=1^+2^ 13=2^+3^ 25=3^+4^

There is a series of numbers: - 2003, - 1999, - 1995, - 1991... Arranged according to a certain rule, then how many items in this series have the smallest sum and what is the minimum value?

Arithmetic sequence, the largest negative number is - 3, n = (- 3 -- 2003) / 4 + 1 = 501
S501=（-2003--3）×501/2=-501000

There is a series of numbers - 2003, - 1999, - 1995, - 1991... Arranged according to a certain rule, then the first () numbers in this series are the smallest?
RT... Good points... Good people

a1=-2003
d=4
When an0, Sn is the smallest
-2003+4(n-1)

If there is a series of numbers: - 2003, - 1999, - 1995, - 1991, arranged according to certain rules, then the sum of the first () numbers in the series is the smallest
A. 500B. 501C. 502D. 503

This series of numbers: - 2003, - 1999, - 1995, - 1991,?, is an arithmetic sequence, the largest negative number is - 3, [(- 3) - (- 2003)] 4 + 1 = 501, so select: B

55 1 / 9 △ 8
Quick calculation

55 1 / 9 △ 8
=(56-8/9)÷8
=7-1/9
=62/9

It costs 1080 yuan to buy 18 sets of desks and chairs. It is known that the price of one desk and three chairs is equal. How much is each desk? How much is each chair?