How many factors of 10800 are perfect squares?a)6 b)12 c)8 d)None of t...
Prime factorization of 10800 = 24 × 33 × 52
If we prime factorise any number which is a perfect square, we would observe that in all cases the exponent of all the prime factors of the number to be even only.
For example, 36 is perfect square 36 = 22 × 32. Here we can see that the exponent of both 2 and 3 are even.
Again, any factor 10800 will be in the form of 2a × b × 5c.
For the factors to be perfect squares, all the values a, b, and c has to be even only.
Or, the possible values which a can take = 0, 2, 4, i.e. 3 values only. Similarly, b can take 0, 2 i.e. 2 values and c can take 0, 2 i.e. 2 values.
Therefore, the different combinations we can have = 3 x 2 x 2 = 12.
Hence, 10800 has 12 factors which are perfect squares.
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How many factors of 10800 are perfect squares?a)6 b)12 c)8 d)None of t...
Answer should be 'd'
bcoz factors of 10800=2^4x 5^2x3^3
2^4=2^0,2^1,2^2,2^3,2^4
similarly, 5^2 =5^0, 5^1,5^2
3^3= 3^0,3^1,3^2, 3^3
and the perfect square -2^0,2^2,2^4,5^0,5^2,3^0,3^2.
no. of factors should be 7....answer is 7
How many factors of 10800 are perfect squares?a)6 b)12 c)8 d)None of t...
Solution:
To find the factors of 10800, we need to factorize it first.
10800 = 2^3 x 3^3 x 5^2
To be a perfect square, a factor must have all the exponents even.
So, we need to find all possible combinations of 2's, 3's, and 5's.
The total number of factors of 10800 is (3+1) x (3+1) x (2+1) = 96.
Now, we need to count the number of factors that have all the exponents even.
The possible combinations are:
2^0 x 3^0 x 5^0 = 1
2^2 x 3^0 x 5^0 = 4
2^0 x 3^2 x 5^0 = 9
2^0 x 3^0 x 5^2 = 1
2^2 x 3^2 x 5^0 = 36
2^2 x 3^0 x 5^2 = 20
2^0 x 3^2 x 5^2 = 45
2^2 x 3^2 x 5^2 = 180
Therefore, there are a total of 1+4+9+1+36+20+45+180 = 296 factors of 10800 that are perfect squares.
Hence, the correct option is (B) 12.