The price of a commodity has been raised by 10% twice in a row, and then it has been sold at a 20% discount. Is it making more or less? How much more or less?

(1+10%)(1+10&)*80%
=1.1*1.1*0.8
=1.21*0.8
=0.968
So make less money
Less earned 1-0.968 = 0.032 = 3.2%

Math problem 15 in Grade 6 of primary school
The food store bought a batch of apples and pears, of which the kilogram of apples accounted for 80% of the total. A week later, only 200 kilogram of apples were sold. At this time, the kilogram of apples still accounted for 75% of the total. How many kilogram of apples and pears do you buy?

Suppose you buy x kg apples and Y kg pears
x=(x+y)*80%
x-200=(x-200+y)*75%
The solution is y = 200, x = 800
My answer is authoritative. They are wrong
the end

The sixth grade students planted trees. One third of the total trees were planted on the first day, two fifths of the total trees were planted on the second day, and eight more trees were planted on the second day than on the first day. How many trees should the sixth grade students plant?
What do you think

8/(2/5-1/3)=120

There are 64 people in a circle, counting clockwise. The first one stays, the second one goes away, the third one stays, the fourth one goes away And so on. In a word, the circle shrinks one by one along the circle, until finally, there is only one person left on the circle, then he is the winner. If you want to win, where should you stand at the beginning?
There are not many problems in the guidance

Of course, it's the first person. It's in the best interests. After No. 2 goes away, No. 3 becomes a new No. 2, and every number will become a new No. 2, with the exception of No. 1, so no. 1 is the winner. If it's the second one, it's No. 64, because it's always the number of the person who is a multiple of 2

Class 6 (1) used to have 49 girls. In the new semester, four girls were transferred out. At this time, girls account for 25% of the class. Now there are girls in class 6 (1)______ People

9-4 = 55-2 = 34 △ 45-23 = 4 △ 215 = 30 (people) 30 × 23 = 20 (people) a: there are 20 girls in class 6 (1). So the answer is: 20

The fruit shop brought in a batch of fruits. Bananas are seven ninth of apples. There are more apples than bananas and fewer bananas than apples

Bananas are seven ninths of apples: bananas = (7 / 9) apples
More apples than bananas?: (apple banana) / banana = [apple - (7 / 9) apple] / [(7 / 9) apple] = (2 / 9) / (7 / 9) = 2 / 7
Is banana less than apple?: (apple banana) / Apple = [apple - (7 / 9) apple] / Apple = 2 / 9
More or less than what, use more or less than what follows

Ask some questions to solve, require a little detailed process. Can answer a few calculate a few. I send integral
It has been known that the number of days required for the master to work alone is equal to the number of days required for the two land cooperations, while the number of days required for the master to work with the land cooperations of B is four times that for the land cooperations of A?
2. If the height of a cuboid increases by 2 cm, it becomes a cube, and its surface area increases by 48 square cm. The surface area of the original cuboid is () square cm
3. The ratio of the divisor to the divisor is 15:7. If the divisor increases by 12, the quotient is 9, and the divisor turns out to be ()
Hope to write the thinking process. I will add 50 points. Guarantee!
I'll get the right answer as early as possible,

1. A: 1 / [(1 / 8) / (1 + 4)] = 40 days
B: 1 / [(1 / 8) / 2 - (1 / 8) / (1 + 4)] = 80 / 3 days
2. Side length = (48 / 2) / 4 = 6cm
Surface area = 6 * 6 * 6-48 = 168cm ^ 2
3. (15x+12)/7x=9
x =1/4
Divisor = 15 * (1 / 4) = 15 / 4

The number on a two digit ten is a, and the expression for the two digit is ()
1.A+3 2.3+10A 3.30+A

(2) Suppose the number of ten digits is 5, then the number of ten digits is 50, that is, 5 * 10 = a * 10

1. There are less than 100 ping-pong balls in the box. If you take three at a time, there will be two at the end. If you take five at a time, there will be three at the end. If you take two at a time, there will be no more than () ping-pong balls in the box?
2. Specify a △ B = 5a-4b, if x △ (5 △ 2) = 14, find X
3. The area sum of the front and top of a cuboid is 209 square centimeters. The length and width of the cuboid are prime numbers in centimeters. What is the cuboid's volume in cubic centimeters?
Please answer within the third! I have to hand it in tomorrow,

1. There are less than 100 table tennis balls in the box, if 3 balls are taken each time, the last difference is 2; if 5 balls are taken each time, the last more than 3; if 2 balls are taken each time, there is no surplus, the maximum number of table tennis balls in the box is (58). 2. A △ B = 5a-4b, if x △ 2 = 14, find X5 △ 2 = 17x △ 17 = 5x-4 × 175x-4 ×

It takes 8 hours for a to go from a to B, and 10 hours for B to go from B to A. now, a and B start from a and B at the same time, face each other, and meet 20 kilometers away from the midpoint. How many kilometers are there between a and B?

Method 1
8:10=4:5
20*2÷(5/9-4/9)=360
The distance between a and B is 360 kilometers
Method 2
Suppose the distance between a and B is LKM
From the meaning of the title
The speed of a is L / 8 km / h; the speed of B is L / 10 km / h
The distance of a is L / 2 + 20 km in opposite direction;
Route B: L / 2-20 km
So: (L / 2 + 20) / (L / 8) = (L / 2-20) / (L / 10)
The solution is: l = 360km

The price of a commodity has been raised by 10% twice in a row, and then it has been sold at a 20% discount. Is it making more or less? How much more or less?