Unit of transformation 1 A workshop processes a batch of parts, and has completed more than 15 parts in one third of the total number. The rest is just 15 parts in one third of the total number. How many parts are there in this batch? There are two stacks of coal, 240 tons in total. One quarter of the coal is transported by a, and the other 40 tons are transported by B. at this time, the two stacks of coal are just equal. How many tons of coal are there?

Unit of transformation 1 A workshop processes a batch of parts, and has completed more than 15 parts in one third of the total number. The rest is just 15 parts in one third of the total number. How many parts are there in this batch? There are two stacks of coal, 240 tons in total. One quarter of the coal is transported by a, and the other 40 tons are transported by B. at this time, the two stacks of coal are just equal. How many tons of coal are there?

1. Let there be x in total
X-(X/3+15)=(X/3+15)/3+15
2X/3-15=X/9+20
X/3=35
X=105
There are 105 parts in this batch
2. If a has x tons, B has 240-x tons
X*(1-1/4)=240-X+40
3X/4=280-X
7X/4=280
X=160
280-160=120
A used to have 160 tons, B used to have 120 tons

How to find out unit 1
I'm ready to do my homework. Help me. I didn't listen in class
Is it absolutely accurate? I want to be right. I don't want to be scolded by the teacher. I am a good student.

In the middle of the sentence, it is a fraction of so and so. So and so in the sentence is unit 1

Unit conversion in grade six

0.15 kg = (150) g 3.001 t = (3) t (1) kg
3.7 square decimeter = (37000) square millimeter 5.80 yuan = (5) yuan (8) Jiao
(15) decimeter = 1.5 meter (4) ton (80) kilogram = 4.08 ton
510 M = (0.51) km, 5 m, 16 cm = (5.16) M
5kg 700g = (5.7) kg 0.95m = (95) cm
4700 M = (4.7) km, 3650 g = (3.65) kg
40.06 tons = (40060) kg, 1.4 square meters = (140) square decimeters
360 M2 = (0.036) ha 7.05 M = (7) m (5) cm
45 kg = (5) kg (450) g
3 km 50 m = (3.05) km (0.5) = 30 minutes
3 kg 500 g = (3.5) kg (2.75) = 2:45
2.78 tons = (2) tons (780) kg
25 = (15) minutes
504cm = (5.04m)
4.2 M = (4) m (20) cm
10 M 7 decimeter = (10.7) M
0.06 km2 = (6) ha
9 kg 750 g = (9.75) kg
8.04 tons = (8) tons (40) kg
24 square meters = (624) square decimeters
0.05 km = (50) M
1250 sq cm = (0.125) sq m
100 ml = (0.1) l
1 ton 70kg = (1.07) tons
102 square kilometers = (102000000) square meters
2.68 L = (2) l (680) ml
1200 m = (1.2) km
4040 kg = (4.04) t
240.3 square centimeter = (2.403) square decimeter
5m 8m = (5.8m)
4.2 square meters = (4) square meters (20) square decimeters

How to find the unit 1 in the application problem of slightly complex percentage, and how to judge whether the problem is plus or minus?

It's very simple. The standard is unit 1. For example, if "a is a fraction of B", then B is unit 1. If a is more or less than B, then B is unit 1. If a is more or less than B, then B is also unit 1

Xiao Wang and Xiao Li set out at the same time from two places 20 kilometers apart, and walked in opposite directions. Xiao Wang traveled 8 kilometers per hour, 9 kilometers less than Xiao Li. After 3.5 hours, how many kilometers were they apart?

20 + 3.5 * (8 + 9 + 8) = 107.5 (km)

4 equations [percent] 2 practical problems [1 unit '1' known, 1 unit '1' unknown]

30%x-15%x=10
40%x-20%x=300
520%x-200%x=300
4.2%x-3.6%x=0.8
There is a box of apples, which received 3.6 tons last year, and this year has increased by 20% compared with last year. How many tons will this year's harvest be
To build a building in a residential area, 40 million yuan was actually used, 30% less than the original plan. How many million yuan was used in the original plan?
Don't you know the main answer

Calculation problem (fractional multiplication)
1 2 3 2005 2006
—*—*—.*——*——
2 3 4 2006 2007

The adjacent numerator denominator can be reduced
one
——
two thousand and seven

2 math problems. I can't figure out *. I hope my friends who are better at math will do me a favor
1. Using the simple algorithm 27 / 5 - [(- 2 + 17 / 5) - (46 / 15-18 / 5)]
2. Calculating | 4 / 7-2 / 5 | - | 3 / 5-7 / 9 | + | 2 / 9-4 / 7 | (| 1 |) is to find the absolute value

First question:
=27/5-[(-10/5+17/5)-(46/15-54/15)]
=27/5-(7/5+8/15)
=20/5-8/15
=60/15-8/15
=52/15
Second question:
Because: 4 / 7 > 2 / 5, 3 / 5

2XY²/2=2YX²/5
2X+5Y=500
This is a system of equations, I need detailed calculation process!

2XY²/2=2YX²/5
Divide both sides by XY
Y=2X/5
Substituting
2X+5Y=500
2X+2X=500
4X= 500
X= 125
Y = 50

Do me a favor, do some calculations,
-|-0.25|×9-5）×4×（-1/25）
（-8）×（1/2-5/4+1/8）
（-1/12-1/36+3/4-1/6）×（-48）
-13×2/3-0.34×2/7+1/3×（-13)-5/7×0.34

The first one is: (- | - 0.25 | × 9-5) × 4 × (- 1 / 25)? If it is
=（-1/4*9-5）*4×（-1/25）
=(-9-20)×（-1/25）
=29/25
（2）=（-8）*（-5/8）=5
(3)=4+4/3-36+8=-68/3
(4)=-13(2/3+1/3)-0.34(2/7+5/7)=-13-0.34=-13.34