1 Calculate the following problem. Note that the calculation is simple.
2/ 19×3+2/ 19× 16
=2/ 19×(3+ 16)
=2/ 19× 19
=2
7/4-( 1/3+3/4)÷2/3
=7/4- 1/3-3/4×3/2
=7/4-3/4- 1/3×3/2
=2/3×3/2
= 1
2. The canteen used 4 tons of coal before, and used 1/8. How many tons are left?
4×( 1- 1/8)
=4×7/8
=7/2 tons
A: There are 7/2 tons left.
3. The school track and field team has 24 female players, with more male players than female players 1/8. How many men are there in the school track and field team?
24×( 1+ 1/8)
=24×9/8
=27 (person)
A: The school track and field team has 27 male players.
There are 20 girls in Class 6 (1) and Class 6 (2). The number of girls in Class 6 (1) is 5/6 of that of boys, and the number of girls in Class 6 (2) is 5/6 of that of boys. How many more boys are there in Class Six (2) than in Class Six (2)?
20÷5/7-20÷5/6
=20×7/5-20×6/5
=20×(7/5-6/5)
=20× 1/5
=4 (person)
Answer: There are four fewer boys in Class Six (2) than in Class Six (2).
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1. Calculate the following questions, which can be easily calculated by simple methods.
5/7× 13/ 1 1-2/ 1 1×5/7
=5/7×( 13/ 1 1-2/ 1 1)
=5/7× 1
=5/7
(2/3+ 1/8)×( 1/2-9/ 19)
= 19/24× 1/38
= 1/48
1-( 1/4+3/8)÷9/ 16
= 1-5/8× 16/9
=3/8× 16/9
=2/3
5/6÷9/ 13+ 1/6÷9/ 13
=5/6× 13/9+ 1/6× 13/9
=(5/6+ 1/6)× 13/9
= 13/9
2. The per capita land area of China is 2/3 less than that of the world. The per capita land area in the world is about 12/5 hectares. What is the per capita land area of China?
12/5×( 1-2/3)
= 12/5× 1/3
=4/5 (hectare)
A: The per capita land area of China is about 4/5 hectares.
3 (1) There are 1.8 million chickens in a breeding base, and the number of ducks is 2/9 less than that of chickens. Abby Mallard keeps tens of thousands of chickens.
1.8×2/9=0.4 (ten thousand)
A: There are 4,000 Abby Mallard chickens here.
(2) There are 1.8 million chickens in a breeding base, and the number of ducks is 2/9 less than that of chickens. How many ducks are there?
1.8-0.4= 1.4 (ten thousand)
A: There are 1.4 million ducks.
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1 A tour group of 32 people once bought a ticket and spent * * * 260 yuan. It is known that each adult ticket is 10 yuan, and each child ticket is 5 yuan. How many adults and children are there in this tour group?
Suppose 32 people are all adults. (treat children as adults)
10×32=320 (yuan)
320-260=60 (yuan)-Assuming more 60 yuan than the actual.
10-5=5 (yuan)-1 children regarded as 1 adults, surpassing 5 yuan.
60÷5= 12 (person)-children
32- 12=20 (person)-adult
A: This tour group has 20 adults, 12 children.
2. A truck can transport ore six times a day in sunny days and four times a day in rainy days. This truck transports ore 38 times a week (7 days). How many days are there sunny and rainy this week?
Let's say it's sunny for seven days. (Think of the rainy days as sunny days)
6×7=42 (stroke)
42-38=4 (stroke)-It is assumed that there are 4 times more than the actual stroke.
6-4=2 (number of trains)-Take the rainy day of 1 as the sunny day of 1, and transport 2 more trains.
4÷2=2 (days)-rainy day
7-2=5 (days)-sunny day
There are five sunny days and two rainy days this week.
On a spring outing, Xiao Ning and Liang Xiao brought 30 yuan money. Xiao Ning used it to go to 6 yuan and Xiao Liang used it to go to 4 yuan, so they had the same amount of money left. How much did Xiao Ning and Xiao Liang bring?
30-(6+4)÷2
=30- 10÷2
=20÷2
= 10 (yuan)
Xiao Ning: 10+6= 16 (yuan)
Liang Xiao: 10+4= 14 (yuan)
A: The original belt of Xiao Ning is 16 yuan, and the original belt of Liangxiao is 14 yuan.
Xiaoming plays a coin toss game. The rule is: throw a silver coin, go forward when it falls 15 step, and want to go back when its back is up 15 step. Xiaoming tossed a coin 10 times, and as a result, he went forward 100 steps. How many times do coins face up? What about backup?
( 15× 10- 100)÷25
=50÷25
=2 (times)
10-2=8 (times)
A: Coins face up 8 times and face up 2 times.