17
15
23
13
17,19,23,29
40/4=10 60/4=15 Then the second prime are between 10 and 15, two prime numbers: 11 and 13 The prime number is between 44 and 52 : 47
15
17... and 19 !
The numbers between 10 and 20 that are not prime are 12, 14, 15, 16 and 18. So 15 is the odd number and the rest are even numbers.
The smallest number that is divisible by 20 and 15 is 60.
It is 19
The smallest prime numbers, after 2, are 3 and 5. 3 x 5 = 15.