Xinhua bookstore has 800 science and technology books, 20% less story books than science and technology books. How many story books?

Xinhua bookstore has 800 science and technology books, 20% less story books than science and technology books. How many story books?

640 copies
800 (1-20%) = 640 copies

Fill in the numbers according to the rules: () (fill in the percentage), () (fill in the score), 0.65%, 76%, 85.100%

(45%) (fill in percentage), (55 / 100 or 11 / 20) (fill in score), 0.65%, 76% and 85% respectively

5x + 1 (52-x) = 10 × 10 to solve the equation

5x+1（52-x）=10*10
So 5x + 52-x = 100
So 4x = 48
So x = 48 / 4 = 12

There are new works on the shelf

In the library, there are some new books on the wooden bookshelf that I like to read

How many days is 4319 hours

4319 hours is 179.96 days
Please comment
~Click comment in the upper right corner, and then you can select satisfied, the problem has been solved perfectly
If you agree with my answer, please accept it in time,
~Your adoption is my driving force~~

Simple calculation of 85 times 5 / 84

85*5/84
=(84+1)*5/84
=84*5/84+5/84
=5+5/84
=5 and 5 / 84

The average height of Xiaoming, Xiaohua and Xiaojun is a centimeter, the average height of Xiaoming and Xiaohua is B, and the average height of Xiaojun is ()

3a-2b

English translation
Please write "30 41 57 65 72 86 98" in English and state their rules of success,

In English, the numbers from 20 to 99 are all ten plus one
The English of 20 to 90 is as follows: (it's basically a number from two to nine plus ty, with some changes)
twenty
thirty
forty
fifty
sixty
seventy
eighty
ninety
So the numbers you give should read like this:
30:thirty
41:forty-one
57:fifty-seven
65:sixty-five
72:seventy-two
86:eighty-six
98:ninety-eight

For an athlete with a weight of 73kg, the skis under his feet are 2m long, 0.1M wide and 12n in weight

The pressure to the ground is equal to the sum of the gravity of the person and the skis, and the pressure is equal to the quotient of the pressure and the stressed area, i.e. (G is 9.8N / kg)
(73kg*9.8N/kg+12N)/(2m*0.1m)=3637N
If G is 10N / kg, then
(73kg*10N/kg+12N)/(2m*0.1m)=3710N

A rectangular basin, 5 decimeters long, 40 centimeters wide and 30 centimeters deep, has a water depth of 20 centimeters,
How many centimeters will the water rise

The volume of water rising is the volume of iron (20 * 20 * 20) / (50 * 40) = 4cm