A math problem multiple ways to solve it .

The first type: if warehouse A stores x tons of grain, then warehouse B stores grain (880-x) tons. Equation: 2 5x = 2 3 (880-x) This is that 2 5 in warehouse A and 2 3 in warehouse B are equal. The equation solves itself.

The second type: first take A as the unit "1". According to what is known there is:

A 2 5 = B 2 3 that is, B = 1 2 5 2 3, known A + B = 880, find the unit "1" with division, the column formula is: 1: A:

2: B: 550 2 5 2 3

330 (tons).

550 (tons).

The third way is to set A 2 5 = B 2 3 = 1

A: 1 2 5 = 5 2

B: 1 2 3 = 3 2

A: B = 5 2:3 2 = 5:3

A = 880 5 (5 + 3) = 550 (tons).

B = 880 3 (5+3) = 330 (tons).

Proportions are also available.

Let A 2 5 = B 2 3 = 1

A: 1 2 5 = 5 2

B: 1 2 3 = 3 2

A is better than B: 5 2:3 2=5:3

A = 880 5 (5 + 3) = 550 (tons).

B = 880 3 (5+3) = 330 (tons).

Start with A as the unit "1". According to the known existence: A 2 5 = B 2 3 that is, B = 1 2 5 2 3, known A + B = 880, find the unit "1" by division, the column formula is: 1: A: 880 (1 + 3 5).

2: B: 550 2 5 2 3

330 (tons).

550 (tons).

A and B go in the opposite direction, so the speed is superimposed, that is, they walk together 230 + 170 = 400km per hour

The total distance is 600km

So after 600 400 = hours, the two will meet each other.

Equation solution: Let us meet after x hours and move in opposite directions.

then (230+170)x=600

400x=600、

x=600÷400

x=so meet after hours.

Equiquantitative relation:

Time A's velocity (230 km h) + time B's velocity (170 km h) = distance between two places (600 km).

Time 230 + Time 170 = 600

Time (230+170)=600

Time 400=600

Time = 600 400

Time = (h).

**Law. <>

The speed of the total distance A and the speed of B.

Every 100km is represented by 1cm, so the length of the lower line is 6cm, and the upper two lines are the sum.

On a 6cm line, draw a dot from the left and a dot from the right.

2cm is exactly half of it.

So draw a dot from the left and then to the right, or from the right and then to the left.

As a result, when a booklet is needed, the two of them go through the whole journey together.

This question is very simple, and the way to answer the question is like this, x, etc.

Specification; i. Specific methods of texting.

Draw a diagram of a collection and solve this problem, and it will be very simple

The last column. 50 + 45 + 40 - 15 - 10 - 8 + 2 * 4 + x = 120 (50 + 45 + 40 is the English, Japanese, French teachers and (there are duplicates) and then subtract their intersection, that is, repeated, and then you will find that the part that the three people have are subtracted twice, so after adding 2 times the number of the three people, and finally adding the foreign language teachers who did not add these three courses, it is equal to 120 foreign language teachers).

The solution is x=10

The answer is 10

There are 50+45+40-15-10-8+4*2=110 teachers who teach these three subjects, and there are 120-110=10 foreign language teachers who do not teach these three subjects. Draw three circles to see better!

Draw a Wayne diagram and just take a look!

There are 50 + 45 + 40-15-8-10 + 4 = 106 teachers who teach English, Japanese, and French

Foreign language teachers who do not teach these three courses have more than 120-106=14 answers, and they are all wrong!

Because of 50+45+40, all three were added 3 times, and later -15-8-10, all three were subtracted 3 times, so in the end, just add a 4!

Solution: Valley-hour electricity consumption x kWh Peak electricity consumption 100-xx=25 valley-hour electricity consumption accounts for total electricity consumption: 25 100=25%.

I'll take a seat first.

You can draw a diagram, in fact, the ab side has been set, and the side cd is really moving on a straight line x=3.

First of all, we can consider the special case, i.e. a rectangle, which can be counted as 6, and when c is (3,5) d(3,1), it can be counted as 9, so that the answer can already be determined as d

You can count the cases of 8 yourself. Hope. ovo

The topic is incomplete, the relationship between AD and BC, and the relationship between BE and AC should be clear.

If AE is perpendicular to BC and BC is over E, assuming AE=3, then QE=2 3 AQ=21

qe/aq=2√7/7

So choose C

Let x people make masks and y people make flowers.

x+y=57

18x=2×10y

Solution: x = Answer: 30 people make masks, 27 people make flowers.

If x students should be assigned to make masks, then 57-x students should make flowers 2*10x=18*(57-x).

x=27,57-x=30

Twenty-seven students should be assigned to make masks and 30 students to make flowers.

set, x people make flowers, 57-x people make masks.

18x=（57-x）×2 ×10

x=30 means 30 people make flowers and 27 people make masks.