In 50 ~ 80, the multiple of 3 is If the title, to the whole

In 50 ~ 80, the multiple of 3 is If the title, to the whole

51、54、57、60、63、66、69、72、75、78
Just add the bits and the tens to a multiple of 3

What are the multiples of 5 in 50 ~ 80? 7, 11, 6, 8. Urgent

5：50、55、60、65、70、75、80；
7：56、63、70、77；
11：55、66、77；
6：54、60、66、72、78；
8：56、64、72、80；

Within 50, a number is not only a multiple of 3, but also a multiple of 5?

It could be 15, 30, 45
The minimum is 15

A four digit number 80? 3 is a multiple of three. How many numbers can I fill in here? If this number is a multiple of both three and nine, how many numbers can I fill in here?

1 4 7

-3, - 1,1, (), 5. Find the rules, and explain them in detail! There are special rewards for 2,5,10,17 (), 37

-3,-1,1,（3 ）,5
Add two to the following numbers
2、5、10、17、（ 26）、37
The number after is 3, 5, 7, 9, 11 more than the number before