1. olympiad math test questions and answers in the second grade of primary school
1. Party A and Party B walked across two places at the same time. Four hours later, they met four kilometers from the midpoint. A is faster than B. How many kilometers is A faster than B per hour? According to the meeting at a distance of 4 kilometers from the midpoint, and the speed of A is faster than that of B, it is known that A walks 4×2 kilometers more than B, and it takes 4 hours to meet. You can work out how many kilometers A is faster than B per hour.
Solution: 4×2÷4
=8÷4
=2 km
A: A is 2 kilometers faster than B per hour.
2, 3 boxes of apples weigh 45 kilograms. A box of pears is 5 kilograms heavier than a box of apples. How much do three boxes of pears weigh?
You can first find out that the weight of 3 boxes of pears is more than that of 3 boxes of apples, plus the weight of 3 boxes of apples, which is the weight of 3 boxes of pears.
Solution: 45+5×3
=45+ 15
=60 kg
Three boxes of pears weigh 60 kilograms.
2. Question and answer of Olympiad Mathematics in the second grade of primary school
1. There are 20 people crossing the river. There is only one boat on the river. The ship can only carry five people at a time. How many people does the boat have to carry to cross the river?
Answer: 20÷4=5 (times)
Summary Although the boat can only carry five people, when the boat reaches the other side and returns, someone must row back, so it can only pass 5- 1=4 (people) at a time, according to this calculation; 20 people walk 20÷4=5 (times)
2. Application questions
There are 42 students in Class One, Grade Six, of whom 20 take part in the math contest and 10 take part in the composition contest. It is known that two students in the class took part in both the math contest and the composition contest. How many people didn't take part in the competition?
Answer: 20-2= 18 (person)
10-2=8 (person)
42- 18-8-2= 14 (person)
It is known that there are 20 participants in the math contest, 10 participants in the composition contest, and 2 participants in both the math contest and the composition contest, so only 20-2 = 18 participants in the math contest. Only 10-2=8 (people) participated in the composition contest;
3. Test questions and answers of Olympiad Mathematics in the second grade of primary school
1. There are two baskets of watermelon. There are 8 watermelons in the first basket, each weighing 6 kilograms, and there are 9 watermelons in the second basket, each weighing 4 kilograms. To make two baskets of watermelons equal in weight, take out () watermelons from basket A and put them in basket B. The answer is 6× 8 = 48 (kg).
9× 4 = 36 kg
48-36 = 12 (kg)
12 ÷ 2 = 6 (kg) 6 ÷ 6 = 1 (only)
2. Counting problem: Students line up to do exercises, with the same number of people in each row and the same number of people in each column. Xiao Ming is the second left, the third right, the first six and the last seven. There are () students doing exercises.
Answer: 2+3- 1 = 4 (pieces)
6+7- 1 = 12 (pieces)
4× 12 = 48 (piece)
4. Question and answer of Olympiad Mathematics in the second grade of primary school
A drink shop stipulates that one bottle of drinks can use three empty bottles. Xiao Liang bought 10 bottles of drinks and replaced them after drinking them. How many bottles of drinks can he drink at most? Dial one: after drinking all, exchange nine empty bottles for three cups, leaving 1 empty bottle. There are only two empty bottles after drinking, which is not enough to change. You can borrow 1 empty bottles from the shopkeeper. Switch back to 1 bottle, and return the empty bottle to the owner after drinking. That's perfect. No empty bottles, no debts. Add up the drinks10+3+1+1= 15 (bottles), and drink at most15 bottles.
Solution1:10+3+1+1=15 (bottle)
A: He can drink 15 bottles at most.
Dial 2: You can also think of it this way: if you only buy two bottles of drinks, after drinking them, borrow 1 empty bottle from the shopkeeper and change it into 1 bottle of drinks. Just return the empty bottle to the owner after drinking it. It is under this rule that you can drink three bottles of drinks as long as you buy two bottles. Xiao Liang bought 10 bottles of drinks and two bottles 102=5 (bottles), so he can drink five or three bottles, 3×5= 15 (bottles).
Solution 2: 102=5 (piece) 3×5= 15 (bottle)
A: He can drink 15 bottles at most.
5. Question and answer of Olympiad Mathematics in the second grade of primary school
Two car drivers will share a large barrel 12kg of gasoline. At present, there are only two empty barrels that can hold 9 kilograms and 5 kilograms. How can they get the same amount of oil? Answer: Divide 12kg gasoline into two parts, each part should be 6kg. Since 5+ 1=6, the key to pour oil is to find a way to pour 1 kg of gasoline first. First, fill an empty 5 kg barrel with oil and pour it into a 9 kg barrel. Then, fill an empty 5 kg barrel with oil and pour it into a 9 kg barrel. At this time, there is 1 kg oil left in the 5 kg barrel. Then pour all the oil in the 9 kg barrel back into the big barrel, pour 1 kg oil into the 9 kg barrel, and finally pour the 5 kg empty barrel directly into the 9 kg barrel. At this time, there is still 1+5=6 (kg) oil in the 9 kg barrel, and 6 kg oil is left in the big oil barrel.
6. Question and answer of Olympiad Mathematics in the second grade of primary school
1, a row of 20 small animals, the number 16 is just a rabbit from left to right, and the number 10 is just a deer from right to left. How many small animals are there in a * *? Answer and analysis:
Because there are 20- 16=4 animals on the right side of the rabbit and 20- 10= 10 = 0 animals on the left side of the deer, there are 20-4- 10=6 animals from the deer to the rabbit.
2. Weight of a barrel of oil 19 kg. Half-eaten oil, barrel weight 12 kg. How much oil did you eat? How many kilograms of oil are there in the oil drum?
Answer and analysis: subtracting the present weight from the original weight is the eaten weight: 19- 12=7 (kg), and the obtained 7 kg is half of the original oil, and the original oil weight is 7+7= 14 (kg).
A: There used to be 14 kg of oil in the oil drum.