2. When one multiplier is expanded to 10 times and the other multiplier is also expanded to 10 times, the product is expanded to () times.
3. 18× 16 means the addition of (), or it can mean () times of ().
4.43×10 = 430, 43× 2 = 86, 430+86 = 516. This is the thinking process of ()× () = ().
judge
1, one factor has a zero at the end, another factor has two zeros at the end, and the product has at least three zeros at the end. ()
2. The product of two numbers must be greater than these two numbers. ( )
3. 20 times of a number is equal to 2 times of this number and then multiplied by 10. ()
4. One multiplier magnifies 10 times, while the other multiplier remains unchanged, and the product is also magnified 10 times. ( )
choose
1, two factors, one is magnified 9 times and the other is reduced 3 times, so the product ().
A expands 6 times, B expands 27 times, C expands 3 times and D contracts 3 times.
2. There are two factors. After reducing by the same multiple, the product is reduced by 16 times. How many times are the two factors reduced? ( )
4 times B8 times C 16 times D32 times
Column calculation
What is the sum of four times 1 and 25 plus 250?
2. Five times a number is 18, which is more than three times this number. What's this number?
Improve ability
1, school chorus, the number of girls is four times that of boys, and there are 42 more girls than boys. How many boys and girls are there in the chorus?
2. The dividend is greater than the divisor 168, and the quotient is 4. What are dividend and divisor?
3. Divider is larger than quotient 144, and divisor is 7. What is the dividend and the quotient respectively?
4. Students donate money to the disabled, and the amount of donation in grade six is three times that in grade three. If you take out 160 yuan from the sixth grade and invest in the third grade, then the sixth grade will donate more 40 yuan than the third grade. How much did the two grades donate respectively?
5, there are two boxes of toys, the first box is 60 more than the second box. If you take three out of the second box, the number of the first box is eight times that of the second box. How many toys are there in two boxes?
6. There are some books on a bookshelf, and there are more books on the second floor than on the first floor 12. If you take six books from the first floor, the number of books on the second floor is four times that on the first floor. How many books are there on the first and second floors?
7. Two barrels of oil, A and B, each have several kilograms of oil. The oil in barrel A is 20 kilograms less than that in barrel B. If 5 kilograms are poured from barrel A and put into barrel B, the weight of barrel B is four times that of barrel A. How many kilograms of oil are there in barrels A and B?
8. In a math contest, * * * has 10 questions, and each question gets a score of 10 if it is answered correctly. Deduct 5 points for not doing or doing something wrong, and Xiao Cong gets 70 points. How many questions did he get right?