Elementary school around people s mathematics, solving, this is the sixth grade mathematics test que

...I'm sorry I thought wrong, I don't know how much the team walked when Xiaoqiang walked to the head of the team. It's 140 to draw a picture yourself.

Solve with a system of quadratic equations.

When Xiaoqiang walked to the head of the team, the team walked x, and when Xiaoqiang walked back from the head of the team, he walked y again before meeting the end of the team.

Xiaoqiang walked from the head of the team to the end of the team.

80x+y=60

The ratio of the speed of the small strong to the speed of the team is certain, and there is.

x/（60+x）=(80-x)/y

The solution yields x=60 and y=40

As can be seen from the picture, Xiaoqiang walked 60+2y

That's 140m.

But if you can't solve this kind of equation in elementary school, you can refer to this answer and think about it, there should be a simpler explanation.

You can imagine that Xiaoqiang didn't go, the team walked 80 meters first, and then Xiaoqiang walked 80 + 60 = 140 meters to the head of the team, and then returned to the end of the team and added 60 to it, so 200 meters.

A total of 160 meters. Xiaoqiang's speed is twice that of the team, and when he reaches the head of the team, the team has walked 60 meters, and Xiaoqiang has run 120 meters; The team walked another 20 meters, and Xiaoqiang ran another 40 meters.

The ratio is 3 to 7, when Xiaoqiang walks from the head of the team to the end of the team, the team continues to move forward, dividing the captain's 60 meters into 10 parts, when Xiaoqiang walks 7/10 of them, the team walks 4/10 at the end, a total of 140 + (60 10)*7

He walked from the end of the team to the front of the team in 60 meters, and from the front to the back of the team it was still 60 meters.

60+60=120 There seems to be a problem with this question, if you ask Xiao Ming one meter and one second, ask Xiao Ming how long he has been gone.

18. .90 points.

19...The elder sister is 25 years old and 1 7 years old. 176/720...A: B = 12:33

21...A takes 11 hours.

22...I guess it's 84 points. Guessed (5 out of 100 + 3 out of 59, in the other 7.) Average 1 down)

How many questions won't, how many will, do you want answers?

50 divided by (6+4) 5 (groups) 5 large boats and 5 small boats.

A1 2 = B1 3 = C3 7

A3 6 = B3 9 = C3 7

It is known that C paid 120 yuan more than A:

Per serving: 120 (7-6) = 120 (yuan).

This TV set paid: 120x(6+9+7)=2640 (yuan).

Let A x, then B 3 x 2, C 7 x (2*3) = 7 x 67 x 6-x = 120

x=7203x/2=1080

7x/6=840

A total of 2640 yuan.

The amount of money paid by A is equivalent to that of C: (3 7) (1 2) = 6 7 C pays: 120 (1-6 7) = 840

A minus: 840-120=720

B pay: 720 * (1 2) (1 3) = 1080 so the total payment of the TV: 840 + 720 + 1080 = 2640

If A pays x, then the money paid by B is 3x 2, and the money paid by C is 7x 6, then there is 7x 6-x=120, x 6=120, x=120*6=720 yuan, and the total amount of money is (x+3x2+7x 6)*720=2640 yuan.

The TV paid 2,640 yuan.

After selling, the difference in sugar is 16 + 20 = 36 kg, accounting for 4 9 of the first batch

So the first batch of white sugar was 81 kilograms.

So the second batch of white sugar has 81-16 = 65 kg.

After selling 20 kg from the second batch of sugar, it is 20 + 16 = 36 kg less than the first batch.

The first batch of white sugar turned out to be 36 (4 9) = 81

The second batch of white sugar turned out to be 81-16 = 65 (kg).

Let the first batch be x, the second batch be x-16, and after selling, the second batch will be x-16-20, then: (x-16-20)=5 9*x

So, x=81

x-16=65

Then: 65 for the second batch

Set the second batch of original x kilograms.

then the first batch has x+16 kg.

So. x-20=(x+16)*(5/9)

x = 65 (kg).

16+20) (1-5 9) = 81 (kg) – the first batch.

81-16 = 65 (kg) – second batch.

Suppose the girl is x person, there is 4x-18=3x+24, there is x=42So there are 42 girls and 4x42-18 = 150 boys.

If there are x girls, the number of boys is expressed as (4x-18) or (3x+24).

So which manuscript is 4x-18 = 3x+24

Calculated x=42

There are 42 female students, and 4x42-18=150 male chain students.