Advertisements
Advertisements
Question
For the following number, find the smallest whole number by which it should be divided so as to get a perfect square number. Also find the square root of the square number so obtained.
1620
Advertisements
Solution
1620 can be factorised as follows.
| 2 | 1620 |
| 2 | 810 |
| 3 | 405 |
| 3 | 135 |
| 3 | 45 |
| 3 | 15 |
| 5 | 5 |
| 1 |
1620 = 2 × 2 × 3 × 3 × 3 × 3 × 5
Here, prime factor 5 does not have its pair.
If we divide this number by 5, then the number will become a perfect square.
Therefore, 1620 has to be divided by 5 to obtain a perfect square.
1620 ÷ 5 = 324 is a perfect square.
324 = 2 × 2 × 3 × 3 × 3 × 3
∴ `sqrt324` = 2 × 3 × 3 = 18
APPEARS IN
RELATED QUESTIONS
Find the square root of the following number by the prime factorisation method.
1764
By just examining the units digit, can you tell which of the following cannot be whole square?
1026
Find the square root the following by prime factorization.
3013696
Find the smallest number by which 147 must be multiplied so that it becomes a perfect square. Also, find the square root of the number so obtained.
Find the smallest number by which 1152 must be divided so that it becomes a perfect square. Also, find the square root of the number so obtained.
A welfare association collected Rs 202500 as donation from the residents. If each paid as many rupees as there were residents, find the number of residents.
Find the square root by prime factorisation method
256
Find the square root by prime factorisation method
9025
Using prime factorisation, find which of the following are perfect squares.
11250
