Ask the prawns to solve the math problem, and the prawn solve a little math problem,,,, This is a bi

Untie. 1.Let the purchase price of Toy A be X yuan, and the purchase price of B toy will be Y Yuan, according to the title.

x+y=40

90/x=150/y

Solving the system of equations yields x=15, i.e., y=40-x=25

The purchase price of a type of toy is 15 yuan, and the purchase price of a type B toy is 25 yuan.

2.Set up M pieces of A toys and n pieces of B toys, so that the total funds of this purchase do not exceed 1,000 yuan, according to the topic.

m+n=48

15m+25n＜1000

Solved n 28

Therefore, when the purchase of B toys is less than 28 pieces, the total purchase funds of the shopping mall do not exceed 1000 yuan (such as the purchase of 27 B toys, the purchase of A toys = 48-27 = 21 pieces, the total purchase of funds = 21 * 15 + 27 * 25 = 990 yuan 1000 yuan, so meet the conditions).

1) Solution: Let the purchase price of toys A and B be x and y respectively, then it will be derived from the title

x+y=40

90/x = 150/y

From the above two formulas, it is obtained: x=15 y=25, that is, type A: 15 yuan, type B: 25 yuan.

2) Solution: Let the number of toys A and B be m and n respectively, then the meaning of the title is obtained:

m+n=48

M can be obtained from the above three formulas m = 23, n = 25 or m = 22, n = 26 or m = 21, n = 27, or m = 20, n = 28, take one of the schemes m = 23, n = 25, that is, the number of purchases of A, B two kinds of toys are 23 and 25 respectively, and the total purchase funds are: 970 yuan.

1) Set the purchase price of each type A and B toys respectively x, yx + y = 40

90/x=150/y

The solution is x=15 and y=25

The purchase price of each type A and B toys is 15 yuan and 25 yuan respectively.

2) A into 23 pieces, B into 25 pieces, a total of 48 pieces.

23x15 + 25x25 = 345 + 625 = 970 yuan.

1) Solution; Let the purchase price of A be x yuan, and the purchase price of B be y yuan x+y = 40; 90 x=150 y gives 5x=3y; x=40-y;200- 5y=3y;8y=200;y=25;x=15 (2) Dissolve into A x pieces, B y pieces. x+y=48,25x+15y=1000.The solution is x=20 and y=28

Set the purchase price A x B y

x+y=40

90÷x=150 ÷y

Solution. x=15

y=25 Number of pieces A A B B

a+b=48

A solution yields a=23

b=25

1. There are three consecutive natural numbers, the sum of the first number and the two numbers is 47, then the third number is (25), and their sum is (72).

2. (Multiple choice) A two-digit number, the number in the single digit and the number in the tenth digit are composite numbers, and they are co-prime numbers, and the maximum number of this number is (98).

a．96 b．99 c．99 d．94

3. (Multiple choice) The two multipliers are reduced to one-third of the original at the same time, and the resulting product (b) a is expanded to 9 times the original b, and b is reduced to one-ninth of the original c unchanged.

1.Let the three numbers be a, a+1, a+2, from the meaning of the title, a+a+1=47, get, a=23, so a+2=25, 23+24+25=72

9 and 4 are coprime and are both sums.

2. The option is given incorrectly If there is 98, it is 983, b

Question 1 25 72

Question 2 d Question 3 Question B

1。。45 is less than 50 [10] 30 is more than 24 [25], 2. There are 40 male teachers and 50 female teachers.

The number of male teachers is 80 of the number of female teachers, the number of female teachers is 125 of the number of male teachers, the number of male teachers is less than that of female teachers, 20 , the number of female teachers is higher than the number of male teachers, and the number of female teachers is the total number of teachers. The original price of the bicycle is 1880 yuan, and the current price is 1598, how many percent has the ** of this electric car decreased? 【 15】％4。。

Xiaobao is 85cm tall this year, 5cm taller than last year. How many percent has Xiaobao's height increased? 【

The current price of the dress is 320 yuan, and the ** of this dress is 80 yuan lower than the original price. How many percent has the price of this dress been reduced from the original? 【

The ratio of A and B is 80:100 What percentage is the number A of? 【 80】 What percentage of the number of A is counted?

How many percent is the number of A less than the number of A? 【 20】 How many percent more than the number of A? ％

Eh, do it yourself, the eyes are spent.

Let's do it anyway, 1· 10% 25%.

LZ should be an elementary school student or a 6th grade.,I've done it for you in elementary school methods.。。。 Here's how it works...

1. Solution: (50-40) 50=10 (30-24) 24=25%.

2. Solution: 40 50=80%.

50 (40+50) It depends on how many digits it is required, but it just works as a matter of common sense).

3. Solution: (1880-1598) 1880=15%.

A: This electric car** is 15% lower.

4. Solution: 5 (85+5) Same as the second question and the fifth question. . . It depends on the requirements of the question and then decides to be accurate to the number of digits.。。。

Answer: Xiaobao has increased in height.

5. Solution: 80 (320+80)=20%.

A: The price of this dress has been reduced by 20% compared to the original.

6. Solution: 80 100=80%.

For the sake of how detailed I've written, there's no way you can't fail mine

In fact, as long as these questions are found to be very easy to do, lz should have just accepted new knowledge and not figured it out, and after doing more questions, it will slowly understand... To be honest, it was really pediatrics for me to do this kind of topic in my second year of junior high school

2πr= r= r=5

The surface area increases by 1 2 * 5 * 6 * 2 = 30cm

Can't roll a cone The distance from the vertex of the cone to the bottom edge is the same The top of the triangle is not the same distance from the bottom of the point.