The World of Numbers
CBSE · Class 9 · Mathematics
Flashcards for The World of Numbers — CBSE Class 9 Mathematics. Quick Q&A cards covering key concepts, definitions, and formulas.
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What are natural numbers?
Answer
Natural numbers are the counting numbers: 1, 2, 3, 4, and so on. They came from counting objects by one-to-one correspondence. Natural numbers are closed under addition, so adding two natural numbers …
प्राकृतिक संख्याएँ क्या होती हैं?
Answer
प्राकृतिक संख्याएँ गिनती की संख्याएँ होती हैं: 1, 2, 3, 4, और इसी तरह आगे। इनका उद्गम वस्तुओं को एक-से-एक संगतता से गिनने से हुआ। प्राकृतिक संख्याएँ जोड़ के लिए बंद होती हैं, इसलिए दो प्राकृतिक संख्या…
एक-से-एक संगतता ने प्राकृतिक संख्याओं की उत्पत्ति में कैसे मदद की?
Answer
गिनती करते समय एक वस्तु का मिलान दूसरी एक वस्तु से किया जाता था। उदाहरण के लिए, एक कंकड़ एक गाय के लिए हो सकता था। यदि लौटती हुई हर गाय के लिए एक कंकड़ हटा दिया जाता, तो बचे हुए कंकड़ गायब गायों को दि…
How did one-to-one correspondence help in the origin of natural numbers?
Answer
One object was matched with one other object while counting. For example, one pebble could stand for one cow. If one pebble was removed for each returning cow, the remaining pebbles showed missing cow…
What is the Lebombo Bone and why is it important?
Answer
The Lebombo Bone was discovered in the Lebombo Mountains between South Africa and Swaziland and dates back approximately 35,000 years. It has 29 notches and is believed to have been used as a lunar ph…
लेबोम्बो बोन क्या है और यह क्यों महत्वपूर्ण है?
Answer
लेबोम्बो बोन दक्षिण अफ्रीका और स्वाज़ीलैंड के बीच लेबोम्बो पर्वतों में मिला था और इसकी तिथि लगभग 35,000 वर्ष पुरानी है। इसमें 29 खांचे हैं और माना जाता है कि इसे चंद्र चरण-गणक या मासिक धर्म कैलेंडर के…
इशांगो बोन क्या है और इसके खांचे क्या दिखाते हैं?
Answer
इशांगो बोन कांगो लोकतांत्रिक गणराज्य में नील नदी के उद्गम के पास मिला था और इसकी तिथि लगभग 20,000 BCE है। इसमें असममित खांचों के तीन स्तंभ हैं। एक स्तंभ संख्याओं को 11, 13, 17, और 19 में समूहित करता ह…
What is the Ishango Bone and what do its notches show?
Answer
The Ishango Bone was found near the headwaters of the Nile in the Democratic Republic of Congo and dates to around 20,000 BCE. It has three columns of asymmetrical notches. One column groups numbers i…
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Sources & Official References
- NCERT Official — ncert.nic.in
- CBSE Academic — cbseacademic.nic.in
- CBSE Official — cbse.gov.in
- National Education Policy 2020 — education.gov.in
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