Let: n is the last page, and a is the odd page that has been torn off.
1+2+3.......+n = 1 133+a+a+ 1
When n=49
2a = 1225- 1 134 = 9 1
A is not an integer.
When n=48
2a = 1 176- 1 134 = 42
a=2 1
A: This book has 48 pages, and the torn pages are 2 1 and 22 pages.
Four identical rectangles and a small square make up a big rectangle. The area of the big rectangle is 49 square meters, and the area of the small square is 4 square meters. How long is the short side of a rectangle?
2 meters or 0.5 meters?
There are only two possibilities:
(The small square has an area of 4 and a side length of 2 meters.)
The first type: four rectangular short sides are merged and connected together; A small square is connected at both ends of the short side of the rectangle. So the short side of a rectangle is equal to the side length of a small cube, which is 2 meters.
The second type: four rectangular long sides are merged and connected together; A small square is connected at both ends of the four short sides of the rectangle. So the short sides of four rectangles are equal to the side length of a small cube, which is 0.5 meters.
There are a group of bees, among which 1/5 falls on rhododendron and 1/3 falls on gardenia. The number of bees is three times the difference between them. They fly to a scaffold made of branches. Finally, there is a little bee flying between jasmine and magnolia. How many bees are there in * *?
thank you
* * * There are 15 bees.
1÷[ 1- 1/5- 1/3-3*( 1/3- 1/5)]= 1÷ 1/ 15= 15
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How to express the root number 5 on the coordinate axis?
In fact, it's very simple: the tools, rulers, compasses,
Root number 5 = (2 2+12) open root number, draw two right angles. The hypotenuse is the root number 5.
Then use the compass to get the length, and then move the compass to the coordinate axis, and that's it.