# Ex.1.2 Q1 Real Numbers Solution - NCERT Maths Class 10

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## Question

Express each number as a product of its prime factors:

(i) $$140$$    (ii) $$156$$    (iii) $$3825$$   (iv) $$5005$$    (v) $$7429$$

Video Solution
Real Numbers
Ex 1.2 | Question 1

## Text Solution

What is known?

A number.

What is unknown?

The expression of the given number as a product of its prime factors.

Reasoning:

Find the prime factors of the given numbers by prime factorisation method and then multiply the obtained prime numbers to get the product of the prime numbers.

Steps:

(i) $$140$$

Prime factors of $$140$$

\begin{align}&=2,\;2,\;5,\;7 \\&={{2}^{2}}\times 5\times 7\end{align}

(ii) $$156$$

Prime factors of $$156$$

\begin{align}&=2\times 2\times 3\times 13 \\ &={{2}^{2}}\times 3\times 13 \end{align}

(iii) $$3825$$

Prime factors of $$3825$$

\begin{align}&=3\times 3\times 5\times 5\times 17 \\ &={{3}^{2}}\times {{5}^{2}}\times 17\end{align}

(iv) $$5005$$

Prime factors of $$5005$$

$=5\times7\times11\times 13$

(v) $$7429$$

Prime factors of $$7429$$

$=17\times 19\times 23$

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