Problems

Here's a basic chart showing what's where in this long list of problems. There are two fully detailed lists in the User Guide:  SDS Topics in Alphabetical Order and SDS Topics in Numerical Order.

TopicStella Number
Visual Problems1000 – 1170
Logical Deduction1180 – 1290, 3750
Arithmetic1300 – 2022
Symbol Manipulation2030 – 2390, 2745, 4100
Algebra Problems2400 – 2500
Analytic Geometry2750 – 2840, 3680 – 3723
Informal Geometry3000 – 3080
Euclidean Geometry3100 – 3650, 3750 – 3850
Trigonometry4000 – 4340
Probability4400 – 4420

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Stella NumberProblem Title
1000.16Telling Time Backwards, Part II
1000.22Floor Tile Reflection no. 2
1000.26Nasty Page Fold
1000.53Stella's Fishpond
1000.54Swapping Places
1000.82Acropolis Pattern
1009.41Squares on a Lattice
1027.12Partition This Shape no. 2
1027.13Partition This Shape no. 3
1040.21The Wigglesworth Apple Trees
1050.11Penny Triangle
1070.33Snails and Details
1079.11Crabcake
1090.22Cube Frames
1090.53Two Views, One Object
1180.44Social Scale of Boojums
1180.45Biology Lesson
1180.84Mixing Wine and Water
1190.17Digital Clock Minutes
1230.41Hot Potato
1230.54Students and Cars
1230.71Chemical Conundrum
1280.11Toad Tales
1280.12Highland Island
1320.11The Number of Digits in a Product
1322.11Giant Powers of 3
1368.21Torture with Fractions
1395.21Radical in Radical
1490.31Tie-Dyed T-Shirts
1510.21Pamela Gore
1540.71Stella's Barbecue
1550.35Sandwiches
1550.38Bananas and Pears
1600.13A Prime Number
1610.12Primes in Product
1610.31Nasty Numbers
1640.41Find the Number!
2050.41Six Nine's Make A Hundred
2070.14Ghanaian Shirts
2070.41Stacking Grapefruit
2070.43Big and Little Cubes
2070.71Next Perfect Square
2070.84Particle Motion
2100.21Symmetric Exponents
2110.11Big Product
2140.11Triple Ratio
2140.31Gear Wheels
2140.71Beakers, Ratio of Acid to Water
2150.11Difference of Reciprocals
2150.22Diminished by a Reciprocal
2150.72Find the Equivalent
2150.81A Horrendous Quantity
2180.11Real-valued Radical
2200.11Positive Integer Solutions: Count Them
2210.11Fraction Inequality
2210.32Fractional Inequality
2210.51In-equali-tease
2210.81An Inequality with Radicals
2211.11Absolutely Unequal
2211.21Product with an Absolute Value
2220.11Timbuktu Post Office
2230.22The Golden Ratio
2230.32A Quadratic Question
2230.62Two Quadratics
2232.11From a Progression to a Quadratic
2250.21Strange Equation
2260.11Huge Difference of Squares
2288.11A Symmetric Equation
2300.11Exponential Equation With Threes
2310.11Fleet Street Market
2310.21Coffee Break
2310.31Intersecting Lines
2310.41Parking
2315.11Equations with No Solution
2410.11A Salesman's Commission
2410.13Bertha's Tax
2410.34Wendy the Chemist
2410.42Pompeii Geothermal Corp. Wages
2420.11Hen and a Half
2420.12Hen and a Half, Variables
2440.32Driving to Atlanta
2440.63Rashon and Santiago
2440.78Figure Eight Racing
2440.82Gabriela and her Chauffeur
2460.15The Year the Old Cow Died
2470.21The Barbell Exchange
2470.62Solar Panel
2480.11A Birthday Present in Dimes and Quarters
2490.11Supermarket Apples
2490.32The Grow'm Good Nursery
2500.61Cows, Sheep, Horses
2500.71Airplane Baggage
2510.31The Add-One-Subtract-One Operation
2580.22If . . . Then . . .
2580.41A Seventh Power Equation
2600.12Postage Function, Using [ ]
2710.11Sum of Digits
2760.21Adjacent Corner of a Square
2761.11A Sum of Slopes
2761.12Collinear Vertices of Squares
2764.11Stella's Fishpond II
2770.21Lines! Intersecting!
2770.31Trisection Points
2788.21Circle through (1989,y)
2850.51What's The Next Term?
2860.51Robot Stones
3060.52Red and Blue Point Triangle
3060.53Red and Blue Point Parallelogram
3060.54Red and Blue Points, Right Angle
3155.61Triangle Cleverness
3310.19A Pentangle
3320.11A Ratio of Areas
3360.21Rectangle Decomposition
3420.24Three Equilateral Triangles
3420.26Area of a Hexagon
3420.27Triangle Area
3420.28Shaded Square Area
3420.51Area of a Regular Pentagon
3420.61Two Triangles and a Square
3420.71Hard Triangle Area
3420.81Intersecting Medians
3440.41First: Trisect the Diameter
3450.21Tetrahedron Inscribed in a Cube
3460.11Split That Triangle!
3470.12Radio Antenna
3470.13Clairbouyant
3500.41Water Pipes Stack
3500.51Gertrude the Goldfish
3550.23Our Whirling, Twirling, Swirling World
3550.51A Wheel Within A Wheel
3560.11Intersecting Chords
3580.11Trapezoid
3750.13Wind Farm Fun Facts
3750.31Yobs, Blobs, and Slobs
4050.12Area External to Two Circles
4050.14From Tangent to Sine
4100.12There's A Cosine In It
4100.21Find a Sine
4120.11Insulating Tape
4200.11Tetrahedron Cutoffs