find the difference between the largest prime number and smallest prime number from 120 to 190.
问题描述：
find the difference between the largest prime number and smallest prime number from 120 to 190.
larget prime number =
smallest prime number =
the requied difference =__________-__________=___________.
for integers that lie between 1 to 10 (excluding 10 itself),subtract the sum of all the prime numbers from the sum of all the composite numbers,find the difference.
composite numbers between 1 and 10:____________________________
prime numbers between 1 and 10:_______________________________
∴
thw difference =___________________________=_______________
答
找出由120到190最大及最小质数差
质数
最大质数 ＝ 181
最小质数 ＝ 127
所要求的相差 ＝ 181 － 127 ＝ 54
在1到10间的整数（不包括10自己）将复合数（非质数）的总和减去质数的总和,找出相差,
1到10间的复合数：4 6 8 9
1到10间的质数：2 3 5 7
∴
相差 （4＋6＋8＋9）－（2＋3＋5＋7）＝10