Teach math problems simply! 2 math problems to teach!

1. (length + width + height) = 80 4 = 20 decimeters. To be able to cut into three identical cubes, the width and height should be equal and three times the length of the cube Therefore: the height and width of the original cuboid should be:

20 (3+1+1)= 4 dm, Length: 4*3 = 12 dm From this, you can calculate the surface area of the original box! 2. Put and become:

Then use the multiplication distributive property. += = =

1) Can be cut into three cubes, must be (two sides are square) length = width or width = height or length = height Assuming width = height = x, then length = 3x (because cut into 3) (3x+x+x) 4=80 x=4 length=3 4=12, width=4, height = 4 s cuboid surface area = [(12 4) + (4 4) + (12 4)] 2 = 224dm Answer: The original surface area of the cuboid is 224 square decimeters (2) The original formula = = = =

1. The unit price is (20x+12y) (20+y).

2. The second one is right, that is, you don't have it: you can get the final result by putting the previous one: 2AB+2BC+2AC

Do your own things, do your own things, and you will improve in the exam.

Solution: (20x+12y (20+y) is the unit price of mixed into assorted sugars.

1。Up to 60%.

The biggest is probably 60% because the last one is only 60% of people who book and can't be more than 60%.

If they order the other two at the same time, this is possible, so up to 60%2. It turned out that the women's pants were only 99 after the price increase, and the original was 90 men's pants after the price reduction was 99 and the original 110

The new income is 198, the old one is 200 losses.

1. At most, I subscribed to "Youth" and subscribed to the other two publications at the same time, 60%, if 60% is 60% of the total number of people who subscribed to publications, there is no way to ask for 2, no. He paid for it.

Women's pants are cheap. 10% of women's pants are less than 1 10 of men's pants

(1)60%

2) Women's pants are only 99 yuan after adding 10%, then the original ** is 90 yuan, and the men's pants are 99 yuan after 10% reduction, then the original ** is 110 yuan, and the income after changing the selling price is 198 yuan, and the previous income from selling a pair of men's pants and a pair of women's pants is 200, obviously losing 2 yuan.

20 liters = 20,000 ml.

radius = 8 2 = 4

Water cup volume = 4 * 4 * cubic centimeters = milliliters.

20000 cups.

After the incision, there are two planes in the middle.

80 = 2 * one of the planes.

80 = 2 * bottom diameter * height.

Then the height is (80 2) Bottom diameter = 40 4 = 10 decimeters, volume = (4 2) * (4 2) * cubic decimeters.

Solution: 1, (8 2) 2 10 = 160 = cubic centimeter) cubic centimeter = cubic meter = liter.

20 cups) A: You can pour about 40 cups.

2. If the height is h decimeter, then 2 4 h = 80

h=10v= (4 2) 2 10=cubic decimeter).

Answer: The volume of the column is cubic decimeters.

Question 1: After drinking 20%, 80% of the milk is left in the cup.

After filling up with water and drinking 50%, the milk drunk accounts for: 80%*50%=40%, so the remaining pure milk, accounting for the capacity of the cup: 80%-40%=40%.

Question 2: (1 5)+x] 2=3 4

Multiply both sides by two to get (1 5) + x = 3 2

The shift yields: x=13 10, which is 13/10.

Question 3: 5 hours 30 minutes = 330 minutes.

Let the original velocity be x, then the velocity on an uneven road is.

Because the late 12 minutes are all delayed on the uneven road, if this road is flat, the original time to walk this road should be: , and the current time to walk this road is:

The difference between the two is 12 minutes, i.e.:

Solution: x=1 km).

So the distance between the two villages is: 330*(1 km).

1.Occupy 2/5 of the cup

Question 3 of 13 I refuse.