JEE Previous Year Question
Number of numbers of the form xxyy which are perfect squares of a natural number.
Topic: JEE PYQ
Answer: 1. Full step-by-step solution below.
Correct answer: 1
Solution
(1)xxyy
Number can be written in the form of y + 10y + 100x + 1000x = 1100x + 11y
11(100x + y) = where p∈N
Now we can say that p is multiple of 11
100x + y =
100x + y = 44, 99, 176, 275,396, 539, 704, 891
Now x & y are natural number from [0, 9]
only possibility
100x + y = 704
y = 4
x = 7
so number is
7744
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