Elementary school math problem solving, elementary school math problem solving

The first stack is equal in number, and the total of two dollars is equal to the total number of five dollars.

The least common multiple of 2 and 5 is 10

The second stack has the same number of sheets, and if there is a piece of 2 yuan, there will be a piece of 5 yuan, and it will be 7 yuan for one piece.

The least common multiple of 7 and 10 is 70, so the minimum for these two stacks is 70 yuan.

But 70 2 = 35 (yuan) [first stack] 35 2 (yuan) is not divisible.

Then choose 70 2 = 140 (yuan).

The total number of the first stack is 140 yuan, 140 2 = 70 (yuan) and the binary is 70 yuan 70 2 = 35 (sheets).

Five yuan is 70 yuan 70 5 = 14 (sheets).

The second stack is also 140 yuan, 2 yuan, 5 yuan, the number of sheets is the same: 140 7 = 20 (sheets), the two stacks are a total of 140 + 140 = 280 (yuan) [minimum], it can also be a multiple of it, 560 840, 1120, etc.

A total of 280 yuan.

The first disc is 5 yuan 14 sheets 2 yuan 35 sheets.

The second disc is 5 yuan 20 sheets 2 yuan 20 sheets.

Set the first stack of 5 yuan has a sheet, and 2 yuan has a b sheet.

Set the second stack of 5 yuan has C sheets, and 2 yuan has D sheets.

2a=5bc=d

2a+5b=2c+5d

5b = 3d 4a = 7c

and c = d to get b = (12 35)a

We know that b is an integer, so b is at least 35, or it can be a multiple of 35.

The previous answer is assumed to be 35.

In this case, the answer is.

A total of 280 yuan.

The first stack is 5 yuan 14 sheets 2 yuan 35 sheets.

The second stack is 5 yuan 20 sheets 2 yuan 20 sheets.

This is elementary school math?!

The first stack is 5 yuan 14 sheets 2 yuan 35 sheets.

The second stack is 5 yuan 20 sheets 2 yuan 20 sheets.

Express speed = 108 km/h).

Time taken to reach place B = (253-108) 90 = 145 90 = hours) (after one decimal place).

c=(abc)/(ab)=(1/6)/(1/5)=5/6, 1/c=6/5

Subtracted = minus + difference, and subtracted + minus + difference = 126, so subtracted = 126 2 = 63, i.e. the sum of difference and subtraction is 63, and the difference is 2 (2+5) 63 = 18

Dividend = Divisor Quotient, Dividend + Divisor + Quotient = 4 Divisor + Divisor + 4 = 154, so Divisor = (154-4) 5 = 30

1.(axb)xc=1/6

axb)x6=1/c

1/c=6/5=

2.A18

Subtracted - Subtracted = Poor.

y-5x=2x

y=7x2x+5x+7x=126

x=9, so the difference is 2x9=18

3.A30

Dividend divisor = 4

If the divisor is x, then the dividend = 4x

x+4x+4=154

x=30, so divisor=30

1/c=ab/abc=(1/5)/(1/6)=6/5

Let a-b=c because a+b+c=126 substitute c to get a=63, b+c=63 c:b=2:5 c=18

Let a b=c a+b+c=154 c=4 so a=4b 4b+b+4=154 b=30

1: Solution: ab=1 5, abc=1 6 , c=6 5, 1 c= one part of c equals 5 6 2:

Solution: 2+5=7,7*2=14,126 14=9,9*2=18, the difference is 18 3: The divisor of the solution is x

4x+x+4=154 ,5x=154-4 ,5x=150 ,x=30 ,divisor is 30 Listen to me!

First answer: 5 6

Second answer:

Third answer: 30.

If you need to explain, give points first.

Hello (

Actually, the question is very simple. We know that we have two fractions for this math problem that we don't know, and they are both the simplest fractions. So we can set the simplest fraction as a b and the other numerator as c.

According to the title known:

a+c）/b＝4/7

a-c）/b＝5/14

Two-way divided: a + c) b 4 7 16 28

a-c）/b＝5/14＝10/28

So b 28

Then the molecular formula: A+C 16

a-c＝10 ②

Equals: a-a+c+c 16-10

2c＝6c＝3a＝16-c＝16-3＝13

then a b 13 28

Suppose the original fraction denominator is 28, the numerator is a, and the number of addition and subtraction is b, then a+b=16, a-b=10

So what is a equal?

Is it (a+b)+(a-b)=16+10

2*a=26

a=13I don't know if you have ever learned a system of binary linear equations.

If it helps, please adopt it

Suppose the required numerator is set to x.

x plus a number = 16

X minus a number = 10, which means that x is the average of these two numbers, which is 13.

The two numbers are averaged, which is the addition of the two and the division by two.

Did you write that number incorrectly?

2 because it is 2b a

Ask how much 4 copies of C are more expensive than 4 copies of A, you can first ask how much is the difference between one book.

B as an intermediate bridge to compare.

If the unit price of exercise B increases by yuan, and the unit price of exercise C decreases by yuan, then the unit price of exercise books B and C is the same" This means that C is more expensive than B.

The unit price of B's exercise book is more expensive than A's."

Therefore, a single copy of C is more expensive than A.

Four is the yuan!