Help solve the problem! Help solve this problem!

In fact, the easiest way to do this kind of problem is to set up unknowns and list systems of equations.

Solution: Let the original pear x kilogram, apple y kilogram, according to the meaning of the topic:

y/(x-80)=5/4

y-210=1/5(x-80)

Solve the equation to get x=280 and y=250

A: The pear originally had 250 kilograms.

Steps to solve a system of equations: (Scratch paper is OK).

Equation 1 yields y=5 4(x-80), substituting equation 2 yields 5 4(x-80)-210=1 5(x-80), and simplifying yield:

5 4x-100-210=1 5x-16, and finally x=280Substituting y=5 4(x-80) gives y=250

There's a place where I don't know if it's my fault or your fault, but what does the question "The rest of the apple is 5 1 of a pear" mean? 5 1 is 5 times, but according to the title, it should be 1 5. I do it by 1 5, and if it's not right, I do it by 5 times.

Solve it with arithmetic: apples.

Pear. Shipped out of pears 80 kg, at this time apples:pears = 5:4.

If another 210 kg of apples are transported, i.e. only 0 to the left, then the remaining apples are 1 5 of pears.

So, the remaining apples = 1 5 pears = 1 5 * 4 5 (the original apples) 4 25 (the original apples), so 210 kg of apples were transported.

= 1-4 25 = 21 25 of the original apple.

Therefore, it turns out that apples = 210 (21 25) = 250 kg.

So, pear = 250 * 4 5 + 80 = 280 kg.

It's 1 5 That's right, you can't calculate it with 5 1, the result is negative.

Procedure: Make the apple x and the pear y.

then x(y-80)=5 4,x-210=1 5*(y-80);

The result is 280.

It was the pear that turned out to have 280.

Let the pear original x kilogram, and the pear original y kilogram.

y:(x-80)=5:4

y-210):(x-80)=1:5

Solution. x=280

y=250

Let pears have x kilograms and apples have y kilograms.

Column equation system (x-80): y = 5:4

x-80):(y-210) = 5:1

The solution is x=430 y=280

Suppose the original pear x kilogram, the original apple y kilogram, according to the question column equation!

y/(x-80)=5/4

y-210=(x-80)*1/5

Isn't it a pear to solve the value of x? Don't tell me you can't solve equations!

280 kg.

Since the ratio of apples to pears is 5:4, if one part is x, then 80 kg of pears will be shipped out, leaving 5x apples and 4x pears. Later, after transporting 210 kg of apples, the apples are 1 5 of pears (you must be mistaken), then the equation can be listed:

5x-210) 4x=[4*(1 5)x] 4x, then 5x-210=4*(1 5)x, then x=50, so 4x=200, plus the 80 kg of pears shipped before, is a total of 280 kg.

Is the title wrong, apples are pears of 5 1??

1 5 bar.

280 bar. First of all, your question is a bit problematic, it should be 1 5, otherwise you can't do it. I did it with 1 5 (one in five).If the remaining apples are 5x, then the pears have 4x, then there are pears (4x+80)kg

Then (5x-210) 4x=1 5 gives x=50, then there is 280kg of pears

The parabola intersects the straight line at a point, indicating that the point is both on the parabola and on the straight line, and bringing (1,b) into the linear equation gives b -1, and then (1,-1) into the parabola equation gives a -1

Because the painting area = the area of the ceiling and surrounding walls - the area of doors and windows = (12 * 9 + 2 * 9 * 3 + 2 * 12 * 3) - 48 = (108 + 54 + 72) - 48

186 (sq.m.).

So, the stucco area is 186 square meters.

2700 (yuan).

Therefore, it costs 2,700 yuan to lay wooden floors.

1), stucco area = 12 9 + 12 3 2 + 9 3 2-48 = 186 (square meters).

2) Floor needs: 250 12 9 = 27000 (yuan).

It is known that the students in the physical education group, the singing group and the calligraphy group each account for 3 of the total number of grades, and it can be obtained that: the total number of grades can be divisible at the same time;

Because the least common multiple of is 84, the total number of students in the grade is a multiple of 84;

It is known that the total number of students in the grade is close to 100, and it can be obtained that there are 84 students in this grade, of which 84 (1 7) = 12 in the physical education group, 84 (1 4) = 21 in the singing group, and 84 (1 3) = 28 in the calligraphy group.

First determine the total number of people, the total number of people should be divisible by 7, divisible by 3, and divisible by 4, and close to 100 no more than a hundred, this number is 84There are 12 in the sports group, 21 in the singing group, and 28 in the calligraphy group.

What should I do with the accounting entries of the above three companies! Thank you! Company A: Borrow: Credit: Related Subjects (This depends on whether the endorsement to Company C is payment or other) is for reference only A,

The following picture is the answer I wrote, please refer to:

The first problem is that the numerator is unchanged, and the denominator is added according to the law of 5, 7, and 9, that is, 4+5,9+7, 16+9. Thus we can get 25+11,36+13.

For the second question, the answer you wrote is correct. The numerator is added by 1 and the denominator by 2.

Third, the numerator is the denominator of the previous term, and the denominator is the sum of the first two denominators.