There are two signals which keep changing their colours continuously according to a pattern. The
first signal S1 remains Red for 5 seconds, then turns Green for the next 7 seconds, then turns Blue
for the next 6 seconds, then Red again for 5 seconds and so on. The second signal S2 remains Red
for 7 seconds, then turns Green for the next 11 seconds, then turns Blue for the next 6 seconds,
then Red again for 7 seconds and so on. If S1 and S2 turn Red simultaneously, then after how much
time (in seconds) will they turn Blue simultaneously for the first time?>???????
A regular pentagon is drawn on a piece of paper. In how many ways can five identical Re.1 coins be
placed on the five vertices of the pentagon if exactly one coin is to be placed on each vertex???
What does the equation x4 – y4 – 2x3 + 2y3 – 2yx2 + 2xy2 = 0 represent?
(a) Two circles
(b) Four straight lines
(c) A pair of straight lines and a circle
(d) None of these
How many positive integer pairs (x, y) satisfy root x + root y = 2003 ?
devanki
(Dev Dave)
43394
if x^2-y^2= 123 find the value of x^2+y^2 given that x and y are natural numbers?
A car runs on four tyres and has one extra tyre. If each tyre lasts for 10,000 km then what is the
maximum distance (in km) that the car can travel using the five tyres?
A function f(x) is defined, for all natural numbers x, as f(x) = 2f(x – 1) + 5.
If f(1) = 1, then what is the value of f(40) – f(39)?
The letters of the English alphabet, in the order A to Z, are made to represent 26 numbers which are
in Arithmetic Progression. The sum of the numbers representing A, C and E is 36 while that of A, C,
E and G is 60. What is the sum of the numbers representing B, D, F and H?
If p is a prime number and w, x, y, z are four natural numbers whose sum is less than p, then
(w + x + y + z)^p – (w^p + x^p + y^p + z^p) is always divisible by
devanki
(Dev Dave)
43399
if x^2-y^2= 713 find the value of x^2+y^2 given that x and y are natural numbers?
rkade
(rk)
43400
This thread is far better than Ganga maiya ki kasam wala thread 
(5x^2-3y)^1000>>sum of all coeffients in the expansion
2^1/2 *4^1/4 *8^1/8......infinity>>???
no of rectangles in 9*9 chessboard??
26jan 1950??
which day??
note>>do not use calendar>> :mg:
3b+7c+i=120
4b+10c+i=164.5
b+c+i=?????????
djscribbles
(Soumya Mukhopadhyay)
43406
Good LR question Please try
12 as lcm of 2 numbers>hw many ways??
ordered?
unordered??
n!=23 zeros>>
no of posible values of n??
