? First, the conventional memory method.
? Remember first that the prime product of 2 and 3, 2 and 3 is 6. Prime numbers within 100 are generally around multiples of 6. For example, 5,7, 1 1, 13,19,23,29,31,37,41,43 ... only 25,35. Therefore, the two numbers before and after the multiple of 6 in 100 must be prime numbers as long as they are not multiples of 5 or 7. According to this feature, you can remember the prime numbers within 100.
? Second, the classification memory method
? We can divide prime numbers within 100 into five types of memory.
? The first category: prime numbers within 20, * * 8: 2, 3, 5, 7,1,13, 17, 19.
? The second category: prime numbers with unit number of 3 or 9 and difference of ten digits of 3, ***6: 23, 29, 53, 59, 83, 89.
? The third category: the unit number is 1 or 7, and the ten digits are prime numbers with a difference of 3, * * 4: 3 1, 37,61,67.
? The fourth category: single digits are 1, 3 or 7, ten digits are prime numbers with a difference of 3, and ***5 digits are: 4 1, 43, 47, 7 1, 73.
? Category 5: There are also 79 and 97 holding numbers.
? A Simple Trial Quotient Method
? Trial quotient is the key to calculate divisor and three-digit division. When the divisor is close to integer 100, you can try the quotient by rounding. But when the divisor is not close to integer 100, the trial quotient is more difficult and sometimes needs to be adjusted several times. In order to help students solve this difficulty, here is a simple way to try out business.
? When the divisor is 4, the mantissa is regarded as an integer hundred. Divide by an integer to get the quotient minus 1, and then try the quotient.
? The name is 1944÷243, which is 4 except for ten digits. Take 243 as the quotient 9 of 200, 1944÷200, and use 8 (9- 1) to try the quotient.
? When the divisor is 5 or 6, the mantissa is rounded to 1, the divisor is regarded as an integer, and the quotient obtained by dividing the integer is added with 1 trial quotient.
? For example, 1524÷254 is 5 divided by dozens, 254 is regarded as 300, 1524÷300 quotient is 5, and 6 (5+ 1) trial quotient is more appropriate.
? With the above trial business method, some can get the exact quotient directly, and some only need to adjust the quotient once.
Question 2: What are the prime numbers from one to one hundred, also called prime numbers? From one to one hundred, there are twenty-five * * *! 2,3,5,7, 1 1, 13, 17, 19,23,29,3 1,37,4 1,43,47,53,59,6 1,67,7 1,73,79,83,89,97
Question 3: What prime numbers are there in1-100, and how many prime numbers are there within * * * 100?
2,3,5,7, 1 1, 13, 17, 19,23,29,3 1,37,4 1,43,47,53,59,6 1,67,7 1,73,79,83,89,97,
***25
Question 4: What are the prime numbers in 50dd100? Hello! There are 10 prime numbers in 50DD 100: 53, 59, 6 1, 67, 7 1, 73, 79, 83, 89, 97. The economic mathematics team will help you solve the problem, please adopt it in time. thank you
Question 5: How many prime numbers are there within100? They are 2, 3, 5, 7, 1 1, 13, 19, 17, 23, 29, 37 respectively.
Question 6: What are the prime numbers from100 to 200? What about 300? Prime table within 300
2 3 5 7 1 1 13 17 19 23 29 3 1 37 4 1 43 47
53 59 6 1 67 7 1 73 79 83 89 97 10 1 103 107 109 1 13
127 13 1 137 139 149 15 1 157 163 167 173 179 / kloc-0/8 1 19 1 193 197
199 2 1 1 223 227 229 233 239 24 1 25 1 257 263 269 27 1 277 28 1
283 293