There is a two digit number, its ten digit number is a, and its one digit number is B. algebraic expression is used to express the sum of ten digit number and one digit number, and the remaining two digits

There is a two digit number, its ten digit number is a, and its one digit number is B. algebraic expression is used to express the sum of ten digit number and one digit number, and the remaining two digits

The value is: 10xa + B

A is the number on ten bits, B is the number on one bit, expressed by algebraic formula, the two numbers are -------,
What's more, if the number on the ten digit of the two digit is exchanged with the number on the single digit, what is the sum of the number and the original number?

Expression: 10A + B
Sum of original number and exchanged number: (10a + b) + (10b + a) = 11a + 11B

For a two digit number, the number on the one digit is 3 larger than that on the ten digit number. Let the number on the ten digit number be X. use the algebraic expression of X to represent the two digit number

Tens: X
Single digit: x + 3
The two digit number: 10x + X + 3 = 11x + 3

It is known that the solution of {7x-8y = - 1,3x-5y = - 17 is {x = m, y = n, m, n between which two continuous integers?

7x-8y=-1 ①
3x-5y=-17 ②
① X 3
21x-24y=-3
② X 7, get
21x-35y=-119
By subtracting the above two expressions, we get
11y=116
y=116/11≈10.5
By substituting y = 10.5 into formula (1), we get
7x-84=-1
7x=83
x≈11.5
So, M is between 11 and 12, and N is between 10 and 11

Solve the equations {3x + 5Y = 49K, 3x-5y = - K (k is a constant)

3x+5y=49k,①
3x-5y=-k②
① + 2, 6x = 48K, then x = 8K
① - 2, 10Y = 50K, then y = 5K

If the equation (K + 1) x ^ K-3 = 5 is a linear equation with one variable, then x=

Because it's one dollar a time, so there must be k = 1
Substitute:
2x-3=5
So: x = 1

Huanhuan and LeLe bought the same exercise books together. Huanhuan bought 6 exercise books, which cost 3.9 yuan; Lele spent 2.6 yuan. How many less did Huanhuan buy than Lele?

First, divide the total price by the quantity = the unit price
3.9/6, equal to 0.65
The unit price is 0.65 yuan
Then divide the total price by the unit price to get the quantity
2.6/0.65=4
Last 6-4 = 2
A: Huanhuan bought two fewer copies than Lele

At the new year's party, Huanhuan and LeLe played a game. The rules of the game are as follows: 1. Each person draws 4 cards at a time, if they draw a square card
Then add the number on the card; if you draw a round card, subtract the number on the card
2. Compare the calculation results of the four cards drawn by the two people, and the smaller ones sing for everyone
Huanhuan draws 1 / 2 of a square, 3 / 2 of a circle, 5 / 2 of a square and 4 / 2 of a circle
Lele draws - 2 of a square, 1 / 3 of a circle, 5 of a circle and - 1 / 4 of a square
Do you know who will sing for you after this game? Please explain why

Huanhuan is: 1 / 2 - (- 3 / 2) + (- 5) - 4 = 1 / 2 + 3 / 2-5-4 = - 7
Lele is: - 2 - (- 1 / 3) - 5 + (- 1 / 4) = - 2 + 1 / 3-5-1 / 4 = - 7 and 1 / 12 (i.e. - 85 / 12)

Huanhuan is four fifths of Lele's age this year. If Lele is three times younger, she will be as old as Huanhuan. How old are Huanhuan and LeLe?

Let Huanhuan age be x years old and LeLe age be x + 3 years old, then x = 4 / 5 (x + 3) x = 4 / 5x + 12 / 5, so Huanhuan age is 12 years old and LeLe age is 12 + 3 = 15 years old

Huanhuan said to Lele, "I'm eight years older than you. Two years later, my age is three times your age."______ I'm 40 years old

Suppose the age of Lele this year is x years old. From the meaning of the title, we can get: (x + 2) × 3 = x + 8 + 2, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 3x + 6 = x + 10, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 2x = 4, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp