There are 560 story books and science and technology books in the library. The number of story books is 1.8 times that of science and technology books. How many story books and science and technology books are there? How many less science books than story books?

There are 560 story books and science and technology books in the library. The number of story books is 1.8 times that of science and technology books. How many story books and science and technology books are there? How many less science books than story books?

Suppose x science and technology books, then the number of story books is 1.8x, the equation is: x + 1.8x = 560 & nbsp; 2.8x = 560 & nbsp; & nbsp; & nbsp; & nbsp; X = 200; 560-200 = 360 (Books); 360-200 = 160 (Books); answer: there are 360 story books, 200 science and technology books, 160 less than story books

There are 1500 science and technology books and story books in the school library, 30% of which are science and technology books. Later, they bought some science and technology books, 40% of which are science and technology books
How many science and technology books have you bought

Original science and technology book: 1500 * 30% = 450
The rest of the books: 1500-450 = 1050
Total number of books: 1050 / (1-40%) = 1750
New science and technology books: 1750-1500 = 250

Science and technology books account for 40% of the total books in the school library, and story books account for 30% of the total books. There are 1200 more science and technology books than story books?

A: there are 12000 books in the school library

567 square meters = () square meters () square decimeters () square centimeters

1.567 square meters = (1) square meters (56) square decimeters (70) square centimeters
Square is 100 times the relationship

It costs 165 yuan to buy 3 undergraduate technology and 6 story books; it costs 150 yuan to buy 6 undergraduate technology and 3 story books. What are the unit prices of science and technology books and story books?

The price of a science and technology book and a story book: (165 + 150) / (3 + 6), = 315 / 9, = 35 (yuan), the price of a story book: (165-35 × 3) / (6-3), = (165-105) / (3, = 60 / 3, = 20 (yuan), the price of a science and technology book: 35-20 = 15 (yuan); a: the unit price of science and technology book and story book is 15 yuan and 20 yuan respectively

The total cost of two kinds of goods is 200 yuan. The price of goods a is set at 30% of the cost, and that of goods B is set at 20% of the profit. Later, the two kinds of goods are sold at 90% of the price, and the total profit is 27.7 yuan?

200 × (1 + 20%) × 0.9-200 = 200 × 1.2 × 0.9-250 = 216-200 = 16 (yuan) (27.7-16) / [(1 + 30%) × 0.9 - (1 + 20%) × 0.9] = 11.7 ^ [1.3 × 0.9-1.2 × 0.9] = 11.7 ^ 0.09 = 130 (yuan), then the cost price of commodity B is 200-130 = 70 (yuan)

13 cm = () decimeter 86 g = () kg 109 decimeter = () m 5350 = () km

13 cm = (1.3) decimeter 86 g = (86000) kg 109 decimeter = (10.9) m 5350 = (5.35) km

There is a question in Lesson 18 "beauty over a hundred years" in Volume 2 of grade 6: "she has changed from a beautiful little girl, a dignified and resolute female scholar, to a new term" radiation "in science textbooks, to a new unit of measurement" Curie "in physics, and to scientific laws, She has become an eternal milestone in the history of science. "This sentence adopts the sentence pattern of" from. To. "This kind of change is not an ordinary change, but ()
Four "becoming" sum up ()

The promotion of the value of life and the leap of the realm of life summarize Madame Curie's immortal achievements in her life

The least common multiple of 12,15,18,24

360

If 4 / 7 of x equals 3 / 4 of Y, then x: y = ()

If 4 / 7 of x equals 3 / 4 of Y, then x: y = (21:16)