Problems of the Week - April 11 to April 17

Rewards for Problems of the week:

5 stars for the correct answer at your level; 10 stars for the next level; 20 stars for 2+ levels up.

Lower Elementary:

Question:  Start with 1. Add 15. Subtract 11. Double it. Add 1. Multiply by 5. Subtract 30. Take away half. What’s the new number?

Upper Elementary:

Question:  It takes Evelyn 8 minutes to jog all the way around a circular path. If Evelyn starts at 6:35 am and jogs around the path exactly 8 times, what time will it be when she’s done?

Middle School:

Question:  24–karat gold is 100% pure gold. How many ounces of pure gold are there in a 15 pound, 16–karat gold bar?

Algebra and Up:

Question: There are two perpendicular lines graphed on a plane. Line A goes through the points (2, 1) and (6, 3). Line B goes through (2, 1) and (x, 5). Solve for x.

Challenge problem to take home. 5 stars for the correct answer. 

On the last day of school, Jamal’s class is building shapes with gumdrops and toothpicks. Jamal wants to make his shapes so that no toothpick has the same colored gumdrop at both ends. This means that any two corners that are connected must have different colored gumdrops.

What is the fewest number of gumdrop colors that Jamal can use to make (i) a triangle? (ii) a square? (iii) a pentagon? (iv) a hexagon?