Question

Express in International number system:
Thirteen lakh five thousand two hundred nine.
(a) Thirty four million, five hundred ninety thousand four hundred thirty.
(b) One million three hundred five thousand two hundred nine.
(c) One million three hundred five hundred two hundred nine.
(d) One three hundred five thousand two hundred nine.

Answer 1

Hint: We will first convert the given number in words into numerals. Then we will use our knowledge of the international number system to convert the numeral into words. And we know that the values of the places in the International system of numeration are Ones, Tens, Hundreds, Thousands, Ten Thousands, Hundred Thousands, Millions, Ten million and so on.

Complete step-by-step answer:
Before proceeding with the question we should understand the concept behind international number system. As per the International numeration system, the first comma is placed after the hundreds place. Commas are then placed after every three digits. The values of the places in the International system of numeration are Ones, Tens, Hundreds, Thousands, Ten Thousands, Hundred Thousands, Millions, Ten million and so on.
We will first convert the given number in words into numerals as follows: Thirteen lakh is equal to 13,00,000. Five thousand is equal to 5,000. Two hundred is equal to 200. Nine is equal to 9.
Now we will add the numerals as shown: \[1300000+5000+200+9=1305209\]. Therefore, the required number is 13,05,209.
We will now convert the number in the International number system, we write the number as follows: 1,000,000 is One million, 305,000 is Three hundred five thousand, 200 is Two hundred and 9 is Nine.
Combining the numbers in words as One million three hundred five thousand two hundred nine.
Hence, the International number system is one million three hundred five hundred two hundred nine. So the right answer is option (c).

Note: Knowing the values of the places in the international system of numeration is important. We can make a mistake in a hurry and write thousand after million instead of hundred so we need to be careful with this.