Math Plane 

Spare parts has comics and random math topics for discussion. Includes questions (and answers), puzzles, and links to other sources.

7/12/13

Step Function

Alfred Hitchcock Presents a 39 Steps Function...

1) The domain of Hitchcock's function is (0, 39). What is the range?

2) Does [[X1]] + [[X2]] = [[X1 + X2]]?  Provide an examples and/or counter-example.

ANSWERS

To learn about step functions, floor and ceiling functions, and more, visit

7-1-15

Letters and Numbers: Consecutive Squared Integers Puzzle

If A, B, C, D, and E are consecutive integers, what are they?

Two Answers

 Algebraic Solutions

6/27/13

Expressing 44

Mr Callahan: "44, Magnus, is a powerful number!"

6/18/13

Trapezoid, Area, and Coordinate Geometry

If the area of the trapezoid is 53, then what is the coordinate (a, b)?

ANSWER

6/7/13

Proportions

Fraction, Repeating Decimal, and Percentage...

5/17/13

"Doing Lines": Diagonals 

What is a diagonal? A line segment connecting two non-adjacent vertices in a polygon.

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Questions:

1) How many diagonals are in an octagon?

2)  How many diagonals are in a regular polygon with 20 sides?

3) What is a general equation for finding the number of diagonals?  (i.e. how many diagonals are in a polygon with n sides?)

ANSWERS

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Math Comic #86 - "Math Junkies" (5-16-13)

5/10/13

Clock Angles

Webcomic #85 - "Clock Wise"  (click lower right corner to view)

Now, it's time for 3 clock angle questions!

1) What is the measure of the angle formed by the hands of a clock at 5:00?

2) What is the measure of the angle formed by the hands of a clock at 7:12?

3) Challenge:  If it is 12:02, when is the next time the minute hand will cross the hour hand?  (round your answer to the nearest second)..

(Note: the answer is not 1:05:00)

Clock sketches are at the right ----->

Answers

Detailed explanations of questions 1 & 2 --  plus more clock angle questions -- in geometry introduction

Detailed explanation of question 3 can be found in Random Places to Visit