USA AIME 1990 1 The increasing sequence 2, 3, 5, 6, 7, 10, 11, . . . consists of all positive integers that are neither the square nor the cube of a positive integer. Find the 500th term of this sequence. 2 Find the value of (52 + 6 ? 43)3/2 ? (52? 6 ? 43)3/2. 3 Let P1 be a regular r-gon and P2 be a regular s-gon (r ? s ? 3) such that each interior angle of P1 is 5958 as large as each interior angle of P2. What?s the largest possible value of s? 4 Find the positive solution to 1 x2 ? 10x? 29 + 1 x2 ? 10x? 45 ? 2 x2 ? 10x? 69 = 0 5 Let n be the smallest positive integer that is a multiple of 75 and has exactly 75 positive integral divisors, including 1 and itself. Find n/75. 6 A biologist wants to calculate the number of fish in a lake. On May 1 she catches a random