ID  NAME  QUALITY  USERS  ACC %  DIFFICULTY C I 

42  Adding Reversed Numbers  48  39841 


25942  Ball sum  27  962 


30826  Bernoulli numbers  2  3 


24998  PLAYING WITH BITS  24  469 


17921  XOR  10  2951 


18294  Problem1  44 


26314  Corn Headache  5  206 


27269  Cube Numbers  22  416 


22403  Divisors of factorial  40  929 


27299  Find Log  2  50 


25311  Candies  3  715 


32445  COUNT JUMPS  3  50 


25583  Easy Odd Sum  2  801 


31  Fast Multiplication  28  3211 


16272  Nanoworld  8 


25008  New Currency Shopping  1  3 


15708  Divisibility  6  3175 


17104  Fun with Sequences (Act 3)  1  678 


17126  Fun with Sequences (Act 4)  2  371 


17481  Fun with Sequences (Act 5)  291 


18011  Fun with Sequences (Act 6)  376 


18012  Fun with Sequences (Act 7)  318 


176  Sum of onesequence  4  604 


22455  SUM OF PRODUCT  27  734 


235  Very Fast Multiplication  7  564 

#simplemath
The problem involves but simple mathematical concepts like arithmetic operations
http://www.basicmathematics.com