Topics
Basic Concepts in Geometry
Angles
Integers
Operations on Fractions
Decimal Fractions
Bar Graphs
Symmetry
Divisibility
HCF-LCM
Equations
Ratio and Proportion
Percentage
Profit –Loss
- Basic Concepts of Profit and Loss
- Profit or Loss as a Percentage
- Total Cost Price in Mathematics
Banks and Simple Interest
Triangles and Their Properties
Quadrilaterals
Geometrical Constructions
Three Dimensional Shapes
- Prism
- Cubes
- Basic Concept of Cylinder
- Pyramid
- Basic Concept of Cone
- Basic Concept of Spheres
Maharashtra State Board: Class 6
Carl Gauss’s Clever Trick
Carl’s Method:
- Paired the numbers:
1 + 100 = 101
2 + 99 = 101
3 + 98 = 101
...
50 + 51 = 101 - So, each pair gives 101, and there are 50 such pairs.
- Total sum = 101 × 50 = 5050
Another way to understand it:
1 2 3 ............ 99 100 (Hundred numbers)
+100 99 98 ............ 2 1 (Hundred numbers)
101 + 101 + 101 + ............ + 101 + 101 (Hundred times)
But this total is double the actual sum, so divide by 2:
`"101 × 100" / "2"`= 5050
Conclusion:
- Carl Gauss found a quick trick to add numbers from 1 to 100.
- His method helps us add long number sequences easily.
