Roses, lilies and tulips cost 16,8 and 1 dollars each, respectively. Amy buys 30 flowers for 300 dollars, with at least one of each type. How many roses does she buy?
Six teams A,B,C,D,E,F play a round-robin tournament over five days. Every team plays once per day and every pair meets once, so there are three games daily. A beats B on day 1; D beats C on day 2; E beats A on day 3; B beats C on day 4. Which team plays A on day 5?
Seven people make these statements about today. A: Yesterday was Wednesday. B: Tomorrow will be Tuesday. C: Tomorrow will be Wednesday. D: The day after tomorrow will be Tuesday. E: Today is Tuesday. F: Today is neither Monday, Tuesday nor Sunday. G: Today is not Saturday. Exactly one statement is true. What day is today?
Combine 2015 equilateral unit triangles to form a quadrilateral. Find the greatest possible perimeter. Editorial assembly convention: triangles have disjoint interiors, meet edge-to-edge, and form one filled quadrilateral.
In the diagram, $ABCE$ is a square of side 20. Points D and F lie on CE and EA, respectively, with $CD:DE=EF:FA=1:2$. Lines BD and FC meet at G. Find $AG$.
A circle is inscribed in a square and circumscribed about a smaller square. The larger square has side 4 cm. Find the area of the smaller square in square centimetres.