7.  Sample Problems and Activities
 Problems of the Week from Kaplan’s Math Circle
lIs there a last prime?
lAre there more decimals than fractions?
lWhat proportion of the powers of two begin with a "7"?
lIs  n(n-1)+ 41  a prime for every whole number n?
lCan a polyhedron have an odd no. of faces and sides?
lWhich numbers are the sum of two squares?
lWhich numbers whose digits are all equal are prime?