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Why choose 100? Why not 43 or 1000?
Last updated at February 12, 2026 by Teachoo
Class 8 (Ganita Prakash - 1, 2 & Old NCERT)
Chapter 1 Class 8 - Fractions in Disguise (Ganita Prakash II)
- Percentage - Definition
- Figure it out - Page 3, 4
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Uses of Percentages
- Percentage of Some Quantity
- Finding Percentage Quickly
- Fractions, Decimals, and Percentages
- Percentages Greater than 100
- Figure it out - Page 12, 13, 14
- Comparing Proportions using Percentage
- Percentage Increase or Decrease
- Profit and Loss
- Taxes
- Figure it out - Page 19, 20
- Growth and Compounding
- Figure it out - Page 22, 23, 24
- Depreciation
- Tricky Percentages
- Finding Mistakes in Percentages
- Figure it out - Page 28, 29, 30
Transcript
Why choose 100? Why not 43 or 1000?WHY THE NUMBER 100? THE PERFECT PERCENTAGE BASE THE BASE 10 CONNECTION 100 Base 10 Power Why not 43? 43? SEAMLESS WITH CLUNKY & DECIMALS! COMPLICATED!THE "GOLDILOCKS" PRINCIPLE (Finding the Sweet Spot)In percentage calculation, why are we so obsessed with 100 ? Reason 1 - The "Base 10" Connection: Our entire number system is Base 10 (1s, 10s, 100s). Because 100 is a power of 10(10×10), it fits perfectly with decimals. 31% is easily written as 0.31 . If we used "per 43 ", converting 0.31 to a fraction out of 43 would be a nightmare! Reason 2 - The "Goldilocks" Number (The Sweet Spot) 10 is too small: "Per 10 "(per decem) loses detail. 9/34 is roughly 2.6 out of 10 . It feels clunky. 1000 is too big: "Per 1000 " (per mille) gives too much detail for everyday life. Saying "264.7 per 1000" is harder to visualize than "about 26% ". 100 is just right: It is large enough to show small differences (like the difference between 26% and 28% ) but small enough that we can visualize it easily.
