5 Years Math Problems!! Urgently urgent!! Math problems, the second volume of the fifth grade

As can be seen from the title, 4 kilograms of apples are more than 4 kilograms of bananas: yuan. But now there are 7 kg of bananas, so the price of the remaining 7-4 = 3 kg of bananas should be equal to yuan.

Therefore, the price per kilogram of bananas is yuan, and the price of each kilogram of apples is yuan. That is, apples and bananas are yuan and yuan per kilogram.

Solution: Because 1 kilogram of apples is more expensive than 1 kilogram of bananas.

So 4 kg of apples is 4* yuan more expensive than 4 kg of bananas.

And because the price of 4 kilograms of red Fuji apples and 7 kilograms of bananas is the same.

So 7 kg of bananas is more expensive than 4 kg of bananas.

That is, 3 kilograms of bananas are yuan, and each kilogram of bananas** is yuan.

then each kilogram of apples is yuan.

Apples are available for $ x and bananas for $ Y.

4x=7y①

x-y=4/7x=y

Substitution. x-4/7x=

x=understand.........

1 kilogram of apples is more expensive than 1 kilogram of bananas.

Then 4 kg of apples is 4 * yuan more expensive than 4 kg of bananas.

Another 4 kilograms of red Fuji apples and 7 kilograms of bananas cost the same.

So 7 kg of bananas is more expensive than 4 kg of bananas.

That is, 3 kg of bananas is yuan.

Each kilogram of banana** is RMB.

then each kilogram of apples is yuan.

1. FRP without cover.

In other words, there are 5 sides on the surface.

Two sides have been given.

The largest of them can be regarded as the bottom.

The other piece is the shorter side of the box.

Cuboidal. Length, width and height.

That is. 6dm

Then find three more pieces of glass! One piece is.

4dm long and wide.

The other two pieces are the same.

6dm long and wide.

DM2, according to the meaning of the title: rectangular iron sheet is 26cm long and 16cm wide, and each corner is cut to a 3cm.

Square. Rule.

The rest of the center is rectangular.

The length is 26-6=20cm

The width is 16-6 = 10cm, then the cuboid.

Length, width and height are.

20cm10cm

3cm。According to the formula for the volume of the box.

20*10*3=600cm2

60 (100%-25%) 80 (yuan) - 60 (100% 25%) 48 (yuan) - 80-60 20 (yuan) - 20 yuan - 20 yuan.

60-48 12 (yuan) - earned 12 yuan.

A: Selling these two different bags is a loss, because you lose more money than you make.

The first cost price = 60 (1-1 4) = 80 yuan, the second cost price = 60 * (1 + 1 4) = 48 yuan, the total cost of the two commodities = 80 + 48 = 128 yuan.

Selling price = 60 * 2 = 120 yuan < 128 yuan.

Loss of 128-120 = 8 yuan.

Let the cost of earning x the cost of loss y

x-60=1/4x x=8060-y=1/4y y=4880+48-(60+60)=8

Lost 8 yuan.

Let the cost of loss be x, then x-60=1 4*x; x=80 Let the cost of not losing money be y, then 60-y=1 4*60;x=45, then the cost is 80+45=125;125-120=5 earned 5 yuan.

The cost of loss is: 60*4 3=80;

The cost of profitability is: 60*3 4=45;

80 + 45 = 125, 60 + 60 = 120, you can know that you lost 5 yuan.

Loss, loss of a quarter of the bag, the original price is 60 (1-quarter) = 80 yuan. Loss of 80-60 = 20 yuan.

The bag that earned a quarter of the original price was 60 * (1 + quarter) = 75 yuan, and earned 75-60 = 15 yuan.

I earned 15 yuan and lost 20 yuan, and I lost a total of 20-15 = 5 yuanAnswer: I lost a total of 5 yuan.

Original price of one: 60 (1-1 4)=80

The original price of the other one: 60 (1+1 4)48

So it's a loss.

1. Fiberglass without cover That is to say, there are 5 surfaces on the surface, and two surfaces have been given, of which the larger one can be regarded as the bottom, and the other is regarded as the shorter face of the cuboid, so the length, width and height of the cuboid are 6dm and 4dm, so you have to find three pieces of glass! One piece is 4dm long and the other two are the same as 6dm long and dm wide

2. According to the inscription: the rectangular iron sheet is 26cm long and 16 cm wide, and each corner is cut off a 3cm square, then the remaining center of the rectangle is 26-6=20cm long and 16-6=10cm wide, then the length, width and height of the cuboid are 20cm, 10cm, and 3cm. According to the formula of the volume of the cuboid, 20*10*3=600cm2

Let's say this batch of coal actually burned for x days.

3/x＝42

A: This batch of coal was actually burned for 42 days.

It is planned to complete kilometers per day.

Kilometers are actually completed per day.

The actual number of days used in days.

Planned to be repaired every day: km).

Actual daily repair: kilometers) days).

Planning efficiency.

Actual efficiency. Actual number of days.

Bean's Sugar 1314, Hello:

Actually repaired every day:

km) actual completion to: days).

1. The volume of this cube is 12 12 12, so I won't be busy calculating it for the time being.

The height after forging is (12 12 12) 18 12 = 8 decimeters.

2. The volume of this fish tank is 8 8 8 = 512 cubic decimeters.

Solution: Let the current girls x people, boys 3 4 * x people.

Original boys: 3 4x-2 people.

Original girl: x+3 people.

3/4x-2=2/3(x+3)

Multiply by 12 at the same time to get:

9x-24=8（x+3)

9x-24=8x+24x=48

A: There are now 36 boys and 48 girls.

Now there are 36 boys and 48 girls.

Let's set the original number of girls to x.

2/3x+2=3/4（x-3）

The solution is x=51

Now there are 51-3 = 48 girls.

The number of male students is 3 4 * 48 = 36.

Let the number of boys be x and the number of girls be y, and the equation of the problem will be xy=2 3 , x+2) (y-3)=3 4 ; x/y=2/3, 4x+8=3y-9 ; x/y=2/3, 3y-4x=17; -x=2/3y , 3y-4x=17; -3y-8/3y=17 --y/3=17 --y=51 x=34

There are 34 boys and 51 girls.

Now there are 34 + 2 = 36 boys and 51 - 3 = 48 girls.

There are x girls and 3 4x boys.

x+3）*2/3=3/4x-2x=48

A: There are 48 girls and 36 boys.

Solution: The number of girls is x, and the number of boys is 2 3x( 2 3x+2) x-3=3 4

8/3x+8=3x-9

x = 51 The number of boys is 51 * 2 3 = 34.

Suppose there were x girls and 2 3x boys

2/3x+2=3/4(x-3)

x=51 Now there are boys: 2 3*51+2=36 people.

Now there are 51-3 = 48 girls.

Let the number of boys be x and the number of girls be y

x=2/3y

x+2)=3/4(y-3)

Bring in :

2 3y+2)=3 4(y-3)===> both sides are multiplied by 44 (2 3y+2) = 3(y-3)====> parentheses 8 3y+8=3y-9====> both sides are multiplied by 38y+24=9y-27 at the same time

y=51x=2/3y=34