K Raj Kishan

CAT Preparation Community 10y ago

Consider four digit numbers for which the first two digits are equal and the last two digits are also equal. How many such numbers are perfect squares?

3

K Raj Kishan 10y ago

Sir, How to solve such questions?

Yuvaraj S 10y ago

Answer is 7744
Only one possibility

Shubham Nagoria 10y ago

Let number be
1000x+100x+10y+y
It would be 11(100x+y).
So right now number is a multiple of 11, So to be a perfect square it should be a multiple of 11^2
So, 11^2 * 2^6 =7744.

(When exponents of the factors of the number are even then it is a perfect square)

Join CAT 2026 course by 5-Time CAT 100%iler

Crack CAT 2026 & Other Exams with Cracku!