August 2019 Puzzles 
1.  a.  It is a four-digit decimal number.
     b.  Each of its digits is divisible by 3.
     c.  It is less than 10 but greater than 1.
     d.  Its tenth digit is its smallest digit.
     e.  Its thousandths digit is its largest digit.
     f.   Each of its digits is different.
     g.  Its one digit is 2/3 of its thousandths digit.
2.  The mean weight of twelve boulders is twenty-five pounds.  Adding another boulder increases the mean weight to twenty-nine pounds.  What is the weight of the thirteenth boulder?
3.  The mean of a list of seven numbers is 45.  If I add two numbers to this list, the mean of the list becomes 37.  What is the mean of the two numbers that I add to the list?
4. a.  It is a six-digit decimal number.
    b.  It has only two different digits.
    c.  Its digits alternate.
    d.  It is less than 100 but greater than 10.
    e.  The quotient of its tenth digit and its thousandths digit is 1.
    f.  The quotient of two of its digits is 0.8.
    g.  Its hundredths digit is not divisible by 5.
6.  If 1 blue equals 3 greens, 6 reds equal 3 blues, and 3 yellows equal 9 reds, then 10 yellows will equal how many greens?
5.  What is unique about 8549176320?