Mr. Zhang has two stamps with 50 marks and two stamps with 80 marks. How many kinds of postage can he pay with these stamps

8 kinds
1 50 80
2 100 130 160
3 180 210
4 260

RELATED INFORMATIONS

1. Let the corresponding points of rational numbers a, B and C on the number axis be as shown in the figure, and simplify | B-A | + | a + C | + | C-B |
2. Use it first___________ The rule transforms subtraction in the mixed operation of rational numbers into_____ And then in use_____ ,_____ The calculation is simple
3. Large and small trucks are used to transport 29 tons of fruits to the city, large trucks are used to transport 5 tons each time, small trucks are used to transport 3 tons each time, and large and small trucks are used to transport several fruits at one time The answer is eight small cars and one big car,
4. The construction site uses three - thirds of the cement in two days, and two - thirds of the cement in the second How many tons of cement are used in two days
5. How to find the factor of a number more convenient
6. Dear friends, how much is 1 and 7 out of 8 minus 7 out of 12?
7. Chicken and rabbit are in the same cage, with 45 heads on the top and 126 feet on the bottom?
8. A desk has three drawers. Each drawer is 55 cm long, 40 cm wide and 12 cm deep. How many square meters of wood do you need to make this desk drawer
9. It is known that the four vertices of a square are o (0,0), a (1,0), B (1,1), C (0,1), and points D and e move on line OC and ab respectively, and OD = be. Let AD and OE intersect at point G, then the trajectory equation of point G is () A. y=x（1-x）（0≤x≤1）B. x=y（1-y）（0≤y≤1）C. y=x2（0≤x≤1）D. y=1-x2（0≤x≤1）
10. A passenger car and a freight car leave from station a and B at the same time, and they meet after 6 hours After the meeting, the two cars continued to move forward at the same speed. It took another four hours for the bus to reach the second place. How many hours for the truck to reach the first place?
11. If A1 = 1, then S4 = () A. 7B. 8C. 15D. 16
12. 1. There is a tank with a square bottom. If its side is unfolded, it is a square with a side length of 60cm. What is the volume of the tank? 2. If the height of a cuboid is increased by 3cm, it will become a cube. At the same time, the volume of the cuboid is increased by 243cm3. How about the volume of the original cuboid?
13. Numerical reasoning 4,3 / 2,20 / 27,7 / 16,36 / 125, () 1,4,13,40121, () The main thing is to write the process clearly
14. 1, number reasoning 5 / 3, 5 / 4, 10 / 8, (), 13 / 12, answer and rule 2, number reasoning 124361251020, (), answer is 71428, find the rule
15. The answer given by number reasoning 2 5 13 38 () is 121 116 106 91 2*3-1=5 5*3-2=13 13*3-1=38 38 * 3-2 = 116 multiply 3 minus 1, multiply 3 minus 2 cycle (there is an error here) 38 * 3-2 = 112
16. Number reasoning: 1,1 / 2,3 / 13,1 / 10,5 / 121 ()
17. 288 to 192 240 to 160 192 to 128 144 to 96 96 to 64 40 to 80 60 to 90 80 to 100 120 to 180
18. Question: put 20, 40, 60, 80, 100, 120, 140, 160, 180 into nine equal squares of the rectangle, so that each direction (transverse direction) is equal
19. Use 20.30.40.50.60.70.80.90 to form two chains. The total number of five numbers is 300
20. Put seven numbers 40, 80120160200240280 in the circle to make the sum of each line equal to the sum of each circle