In $\Delta$ ABC, BD and CE are prependicular to AC and AB respectively. If BD = CE, then $\Delta$ ABC is
Chords AB and CD of a circle intersect at E. If AE = 9 cm, BE = 12 cm and CE = 3, then the length of DE is
PQRS is a square with side 10 cm. A, B, C and D are mid-points of PQ, QR, RS and SP respectively. Then the perimeter of the square ABCD so formed is
Two sides of a parallelogram are 20 cm and 25 cm. If the altitude corresponding to the sides of length 25 cm is 10 cm, then the altitude corresponding to the other pair of side is
There are five numbers. HCF of each possible pair is 4 and LCM of all the five numbers is 27720. What will be the product of all the five number ?
A person sold his car at a profit of 8$1\over 2$ %. If he had sold it for Rs. 20000 more, he would have gained 21%. Find the cost price of the car.
A certain sum is certain time become Rs. 500 at the rate of 8% per annum simple interest and the same sum amount to Rs. 200 at the rate of 2% simple interest in the same duration. Find the time
Two villagers are 2 km apart. If the angles of depression of these villagers when observed from a plane are found to be 45° and 60° respectively. Then the height of plane is
A cone of height 7 cm and base radius 1 cm is carved from a cuboidal block of wood 10 cm $\times$ 5 cm $\times$ 2 cm. Assuming $\pi$ = $22 \over 7$, the percentage wood wasted in the progress is
What must be added to $1\over y$ to make it equal to y?