The greatest 4-digit number which is a perfect square is

The speed of two trains are in the ratio 6 : 7. If the second train covers 364 km in 4 hours, then what is the speed of the first train?

If the 5-digit number 535ab is divisible by 3, 7 and 11, then what is the value of (a² - b² + ab)?

A man purchased 7 bags of rice at the rate of  ₹ 800 each, 8 bags of rice at ₹ 1000  each and 5 bags of rice at the rate of  ₹ 1200 each. What is the average cost of one bag of rice?

What is the simplification value of $${cotA+tanB}\over{cotB+tanA}$$?

$$ {3tan^{2}30°}-{4\over 3}{sin^{2}60°}- {1\over2}{cosec^{2}45°}+{4\over3}{sin^{2}90°=?}$$

In ΔABC, ∠C=90° and CD is perpendicular to AB at D. If AD/BD=$$ {\sqrt{k}}$$, then AC/BC=?

 if $$\sqrt { 11- 3\sqrt { 8}}=a+b\sqrt { 2}$$, then what is the value of (2a+3b)?