square root of 1500k.How to solve this Elementary Maths question?
Find the prime factorization of 1500.
1500 = 100 * 15 = 10^2 * 3 * 5 = 2^2 * 3^1 * 5^3
A perfect square will have all even exponents in the prime factorization. The smallest number you can multiply to make them even is 3 * 5 = 15
k = 15
1500 k = 100(15k) = the 100 is a square so (15k) must be as square works is k = 15
1500k = 100*(15k)
In order for 1500k to be a perfect square, both 100 and 15k must be perfect squares where 15k =/ 100
Since 100 is already a perfect square (ie 10^2) we need not worry about it
Now 15k must be a perfect square. The smallest multiple of 15 that is a perfect square is 15 (ie 15*15 = 225), therefore the smallest possible value for k is 15.
Hope that helped =D
on factorizing - 1500 = 2x2x5x5x5x3
so k=15 i.e. (5x3)
Write down 1500 as product of its prime factors (other than 1) :
1500 = 2 * 2 * 3 * 5 * 5 * 5
Now count how many times each prime factor appear in above product. For number to be a perfect square each factor should appear even number of times. We can see that factor 2 appears 2 times (even number) but 3 appears once (odd number) and 5 appears three times (also odd number). To make perfect square out of 1500, we should multiply it by 3 (to make factor 3 to appear twice) and by 5 (to make 5 appear four times in total). Therefore number
1500 k = 2 * 2 * 3 * 5 * 5 * 5 * k
is perfect square if k=3*5=15
The answer is k=15
1500k=100*15k
=100*15*15=10*15=150
there fore 15 is the answer
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