The average weight of parts a, B and C is 31 kg. The weight of parts A is 1 kg less than that of parts B and C, and 2 kg more than that of parts B How many kilos does each part weigh?

31*3=93
A = (93-1) / 2 = 46
B = (46-2) / 2 = 22
C = 93-46-22 = 25

Look at the following numbers: one half, one sixth, one twelfth, one twentieth. What's the ninth? What's the fourteenth?

Rule: 2 = 1 * 2, 6 = 2 * 3, 12 = 3 * 4, 20 = 4 * 5
Odd items are positive and even items are negative
It is inferred that the ninth is 1 / 90 and the fourteenth is - 1 / 210

The average weight of the three objects is 31 kg. The weight of object a is 1 kg lighter than that of object B and object C. the weight of object B is 2 times as heavy as that of object B. how many kilogrammes are each of the three objects

Ingenious use of substitution, a = 46, B = 32, C = 15
The total weight is 31 × 3 = 93kg
A + 1 = B + C
A + A + 1 = a + B + C = 93
So a = 92 △ 2 = 46 kg
B = 2, C + 2
B + C = 3 C + 2 = 93-46 = 47
So C = (47-2) △ 3 = 15
B = 32

The sum of two numbers is equal to 7 and 1 / 2, the difference between two numbers is equal to 5 / 6, and the large number is several percent more than the decimal

Let the large number be x and the decimal number be y
Then x + y = 15 / 2
x-y=5/6
The solution is x = 25 / 6, y = 10 / 3
(x-y)/y=(25/6-10/3)÷10/3=5/6×3/10=1/4=25/100=25％
A: large numbers are 25% more than decimal numbers

Six cases weigh 15 kg, 16 kg, 18 kg, 19 kg, 20 kg, 31 kg. Two customers buy five cases, one of which weighs twice as much as the other. How many kg does the remaining one weigh
15+16+18+19+20+31=119
The remaining 15kg: 119-15 = 104104 / 3 = 34.6, that is to say, a customer bought 34.6
Similarly, the remaining 16 kg: 119-16 = 103; the remaining 18 kg: 119-18 = 101; the remaining 19 kg: 119-19 = 100; the remaining 31 kg: 119-31 = 88
The remaining 20kg: 119-20 = 99, one customer bought 33, the other bought 66
33=15+18
66=18+19+31.
That is to say, one customer buys 15kg and 18kg, and the other buys 16KG, 19kg and 31kg
Why divide by three? I know it's three times

Because two customers buy five cases, one is twice as heavy as the other
That is to say, if one customer takes one share, the other takes two
1 + 2 = 3. So divide by 3

Two fifths of a meter is 60 meters. Five sixths of a 1500 gram is () gram. One half of a number is 18, and five ninths of it is ()
There are 100 red balloons and yellow balloons. One third of red balloons are 16 more than one tenth of yellow balloons. How many red balloons and yellow balloons are there?

Two fifths of (150) meters is 60 meters. Five sixths of 1500 grams is (1250) grams. One half of a number is 18, and five ninths of it is (20). There are 100 red balloons and yellow balloons. One third of red balloons are 16 more than one tenth of yellow balloons. How many red balloons and yellow balloons are there

There are two barrels of oil. The weight of barrel a is 23 times that of barrel B. barrel B is 5 kg more than barrel A. how many kg does barrel B weigh?

5 ÷ (1-23) = 5 ÷ 13, = 15 (kg). Answer: B barrel of oil weighs 15 kg

(1 / 2 + 1 / 3) × 1 / 4 - 1 / 6=

=1/2×1/4+1/3×1/4-1/6
=1/8+1/12-1/6
=3/24+2/24-4/24
=1/24

Which weighs a kilogram of iron or a kilogram of cotton?

It seems that iron is the same weight. If you look at it carefully, it's actually one kilogram. One kilogram of iron has the same mass as one kilogram of cotton and contains the same amount of substance

(1 + Half + one third + one fourth) × (half + one third + one fourth + one sixth) - (1 + Half + one third + one fourth)
1 / 2 + 1 / 5) x (1 / 2 + 1 / 3 + 1 / 4)

I'm glad to see the title of the building owner for you. I think there may be a mistake. It's adding 1 / 5 instead of 1 / 6. Otherwise, we can't use a simple algorithm in the end. Let's make both kinds of possibilities for the building owner. Let's check by ourselves: if it's (1 / 2 + 1 / 3 + 1 / 4 + 1 / 5), the original formula is: (1 + 1 / 2 + 1 / 3 + 1 / 4)

The average weight of parts a, B and C is 31 kg. The weight of parts A is 1 kg less than that of parts B and C, and 2 kg more than that of parts B How many kilos does each part weigh?