
Large numbers like lakh and crore are very common in our daily life in India. You must have heard people talking about one lakh rice varieties or population of cities in lakhs and crores. But what does one lakh actually mean? How big is this number really?
A farmer once heard that there were one lakh different varieties of rice. In earlier times, farmers used to preserve many different rice varieties. But now, only few varieties remain with us. That’s why seed banks are working hard to collect and save these indigenous rice seeds.
One lakh is definitely a large number to understand properly. When we compare large numbers with things we know, it becomes easier to understand how big or small they actually are.
A Lakh Varieties
One lakh means 1,00,000 – that’s number 1 followed by 5 zeros. To understand this better, let’s see:
- Largest 4-digit number = 9999
- Smallest 5-digit number = 10,000
- Smallest 6-digit number = 1,00,000 (this is one lakh)
Now think about eating rice. If you eat one different variety of rice every day, how long will it take to taste all one lakh varieties? A year has 365 days (we are not counting leap years). So if you want to taste one lakh varieties, you will need 1,00,000 ÷ 365 = about 274 years! That’s much more than a human lifetime.
Is One Lakh a Very Large Number ?
This depends on what we are comparing it with. Let’s see some examples:
When one lakh seems very large:
- One lakh different rice varieties is really a lot
- Living for one lakh days means living for 274 years
- If one lakh people stand in a line, the line will stretch for 38 km
When one lakh seems small:
- A big cricket stadium can hold more than one lakh people
- Human hair on head can be 80,000 to 1,20,000 in number
- Some fish can lay one lakh eggs at one time
So you see, large numbers can seem big or small depending on what we are talking about.
Reading and Writing Numbers
In India, we use a special way to write large numbers with commas. This is called Indian place value system. We put commas following a 3-2-2 pattern from the right side.
For example:
- 12,78,830 = twelve lakh seventy-eight thousand eight hundred thirty
- 1,00,000 = one lakh
- 10,00,000 = ten lakh
These number names help us read large numbers easily. This Indian system is also used in many other South Asian countries like Nepal, Bhutan etc. The words “lakh” and “crore” come from old Sanskrit language.
Land of Tens
Let’s study some calculators with special buttons:
Different Calculator Types:
- Thoughtful Thousands: Has only +1000 button
- Tedious Tens: Has only +10 button
- Handy Hundreds: Has only +100 button
- Creative Chitti: Has buttons +1, +10, +100, +1000, +10000, +100000, +1000000
Systematic Sippy always tries to use minimum button clicks. There are different ways to reach the same number, but the minimal clicks method relates directly to place value notation.
Of Crores and Crores!
One crore is 1,00,00,000 – that’s 1 followed by 7 zeros. One crore equals 100 lakhs.
One arab is 1,00,00,00,000 – that’s 100 crores.
Indian vs American System:
Indian System | American System |
---|---|
One lakh = 1,00,000 | Hundred thousand = 100,000 |
One crore = 1,00,00,000 | Ten million = 10,000,000 |
One arab = 1,00,00,00,000 | One billion = 1,000,000,000 |
Indian system groups digits in 3-2-2 pattern while American system uses 3-3-3 pattern.
Exact and Approximate Values
Sometimes we need exact numbers (like money transactions), but other times approximations work fine.
Rounding Methods:
- Rounding up gives higher number
- Rounding down gives lower number
- Example: Population of 76,068 can be rounded to 75,000
We can compare large numbers to familiar things. Like Statue of Unity is 180 meters tall and Kunchikal waterfall is 450 meters high.
Patterns in Products
Multiplication has some interesting shortcuts:
Multiplication by 5:
- 116 × 5 = (116 × 10) ÷ 2 = 1160 ÷ 2 = 580
Patterns in special multiplications:
- 11 × 11 = 121
- 111 × 111 = 12321
- 1111 × 1111 = 1234321
When we multiply two 2-digit numbers, we get either 3-digit or 4-digit product. The number of digits in product relates to the multiplicands.
Fascinating Facts about Large Numbers
Large numbers appear everywhere in real life:
- Purandaradasa composed thousands of kirtanas
- Earth-Sun distance is about 15 crore kilometers
- Amazon River discharges lakhs of liters water per second
- Blue whales can weigh up to 15 lakh kilograms
- One gram of soil contains millions of bacteria
Comparing these large numbers to things we know helps us understand their size better.
Did You Ever Wonder…?
Some interesting questions about large numbers:
Can Mumbai’s population fit in one lakh buses? One lakh buses can hold about 50 lakh people, but Mumbai’s population is more than one crore. So we need more buses!
If you travel 100 km every day, can you reach Moon in your lifetime? Moon is about 3,84,400 km away. In 100 years, you can travel 100 × 365 × 100 = 36,50,000 km. This is less than Moon’s distance, so you cannot reach Moon even in 100 years of daily travel.
Questions and Answers
Q1: If a person ate 3 varieties of rice every day, can they taste all lakh varieties in 100 years?
Days in 100 years = 365 × 100 = 36,500 Varieties in 100 years = 36,500 × 3 = 1,09,500 Since 1,09,500 > 1,00,000, yes they can taste all varieties.
Q2: How much less than one lakh is 75,000?
Difference = 1,00,000 – 75,000 = 25,000
Q3: Write 5,04,085 in words:
Five lakh four thousand eighty-five
Q4: How many times should +1000 button be pressed to show one lakh?
1,00,000 ÷ 1000 = 100 times
Q5: Compare 500 lakhs and 5 million:
500 lakhs = 5,00,00,000 5 million = 50,00,000
So 500 lakhs > 5 million
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