"After the Yushu earthquake in Qinghai Province on April 14, 2010, a school donated 3000 books in aid activities to schools in the disaster area. Due to the positive response of students, it actually donated 3780 books, of which the primary school gave 20% more than the original plan, and the junior middle school gave 30% more than the original plan. How many books did the primary school and junior middle school give each?" this is a math problem in the winter vacation of grade seven, I can't copy a word No! It should be all hit! Please give me face!

"After the Yushu earthquake in Qinghai Province on April 14, 2010, a school donated 3000 books in aid activities to schools in the disaster area. Due to the positive response of students, it actually donated 3780 books, of which the primary school gave 20% more than the original plan, and the junior middle school gave 30% more than the original plan. How many books did the primary school and junior middle school give each?" this is a math problem in the winter vacation of grade seven, I can't copy a word No! It should be all hit! Please give me face!

According to the meaning of the title, there are x original plan books for primary school and 3000-x original plan books for junior middle school
（1+20%)x+(1+30%)(3000-x）=3780
1.2x+3900-1.3x=3780
－0.1x=－120
x=1200
3000-x=1800
A: the school's primary school plans to give 1200 books, while the junior high school plans to give 1800 books

The edge length of a cube is 3 * 10 ^ 2mm
(1) What is its surface area in square meters? (2) what is its volume in cubic meters?
(a + 1) ^ 3 =?, can we use the complete square formula

(1) How many square meters is its surface area? 6 × (3 × 10 & sup2;) = 18 × 10 & sup2; = 1.8 × 10 & sup3; square millimeter (2) how many cubic meters is its volume? (3 × 10 & sup2;) & sup3; = 27 × 10 ^ 6 = 2.7 × 10 ^ 7 cubic millimeter. (a + 1) ^ 3 =?, can we use the complete square formula

Seventh grade students play checkers. The rules of the game are as follows: first draw a number axis, and the pieces fall on A0 point on the number axis. The first step is to jump a unit length A1 from A0 to the right, the second step is to jump 2 unit lengths to A2 from A1, and the third step is to jump 3 unit lengths to A4 from A2 to the right After 50 steps, the chess piece falls on the number axis A50. If the number represented by A50 is 26, what is the number represented by A0?

-If A1 jumps one unit length, A2 jumps two units length to the left, A3 jumps three units length to the right, we can see from the title that odd number jumps to the right, even number jumps to the left, right jump is addition, left jump is subtraction (you can draw a number axis to understand). If A0 is x, then x + 1