Lets arrange the letters alphabetically = AAANRSTTW
Words starting with A = 8!/(2!*2!) = 10080
Words starting with N = 8!/(3!*2!) = 3360
Words starting with R = 8!/(3!*2!) = 3360
Words starting with SA = 7!/(2!*2!) = 1260
Words starting with SN = 7!/(3!*2!) = 420
Words starting with SR = 7!/(3!*2!) = 420
Words starting with ST = 7!/(3!) = 840
Words starting with SWAA = 5!/(2!) = 60
Words starting with SWAN = 5!/(2!*2!) = 30
Words starting with SWAR = 5!/(2!*2!) = 30
Words starting with SWATAA = 3! = 6
Words starting with SWATANA = 2! = 2
Words starting with SWATANR = 2! = 2
Words starting with SWATANTA = 1 = 1
And next word is SWATANTRA so + 1
Two trains are running in opposite directions on parallel tracks. Train running with speed 60 Km/hr has 240 meter length and the second train running with speed of 40km/hr has 290 meter length.
What is the time taken by the faster train to completely pass through the length of slower train (i.e from front to rear)?
We are calculating the time taken by the faster train to completely pass the length of slower one.
Hence, distance = length of the slower train + length of faster train = 240+290 = 530 meter
Two ships are sailing in the sea on the two sides of a lighthouse. The angle of elevation of the top of the lighthouse is observed from the ships are 60Β° and 30Β° respectively. If the lighthouse is 144 m high, the distance between the two ships is:
OPtion
1) 312.55 m
2) 322.55 m
3) 362.55 m
4) 302.55 m
5) 342.55 m
6) 352.55 m
7) 332.55 m
8) 372.55 m
9) 382.55 m
10)None of these
Solution
Let AB be the lighthouse where A is the bottom point of light house and C and D be the positions of the ships.
Then, AB = 144 m, Angle ACB = 60Β° and angle ADB = 30Β°.
AB/AC = tan 60Β° = sq root(3)
=> AC = AB / sq root(3) = 144/3^(1/2) = 48*3^(1/2)
AB/AD = tan 30Β° = 1/sq root(3)
=> AD = AB*sq root(3) = 144*3^(1/2)
3 solid spheres of radius 7 m, 5 solid cylinder of radius 5 m, height 3 meter and 7 solid cones of radius 3 m, height 7 m are melted to form a bigger solid sphere. What is the radius of this bigger solid sphere in meters?
P can do a work in 17 days. Q can do the same work in 8.5 days and R can do the same in 25.5 days. Q and R start the work and leave after 3 days. P finishes the remaining work in X days. What is the value of X?
OPtion
1) 9.0 days
2) 8.0 days
3) 8.5 days
4) 10.5 days
5) 10.0 days
6) 11.0 days
7) 12 days
8) 12.5 days
9) 7.0 days
10) None of these
Solution
Amount of work done by Q and R in 3 days = 3*(1/8.5 + 1/25.5) = 3*2*4/51 = 8/17
Amount of work remaining after 3 days = 9/17
Amount of work done by P in 1 day = 1/17
So for 1/17 work P takes 1 day
Hence for 9/17 work P would take (1/(1/17))*8/17 = 9 days
The wonder is not that mathematics describes the world so well but that it describes it at all.
Unknown
Maths is just like a stone if u will uttern it therefore u can acheive the zenith of success but if u will not in that case it will become headache for u...