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Junior high school math problem solving is not
1)

Let x people produce parts a and y people produce parts b.

Then: x+y = 62; 12x/23y=3/2

Substitute x=69/24y in formula 2 into formula 1 and y= 16, so x=46.

2)

The profit from selling 1 product is 4-2.3-4* 10%= 1.3 yuan, and the profit from producing 20W pieces a year is 26W yuan.

The first year's loan is 40W, which will be repaid at the end of the year, with a profit of 260,000, which is not enough;

At the end of the second year, 46 * (1+15%) = 529,000 yuan, and the second profit was 520,000 yuan, which is not enough.

You can pay it off in the third year.

3)

3000*( 1+5%)=3 150

(4500-3 150)/4500=30%

(4500-3000)/4500=33.3%

95%- never fully understood the meaning of the topic.

4)

It takes x, y and z days to produce a, b and c parts respectively.

Then x+y+z=63.

300x=500y=600z

According to Equation 2, Y=3/5x and z= 1/2x.

Substituting 1 gives x=30, so Y= 18 and z= 15.

5) Simplify the equation and get 2x=3-4m.

Therefore, if x is a positive integer, we can assume that x= 1, 2, 3 in turn, and get different m.

If x < =2, 2x

6)

|x-2| >=0,(3x-y+m)^2>; =0

So | x-2 | = 0, (3x-y+m) 2 = 0.

So x=2, so 6+m-y=0.

If y & gt=0, then 6+m > =0, that is, m>= -6.

If y < -2, then 6+m.