#131 - Number Series Question
Identify the next two numbers in this series?
101, 112, 131, 415, 161, 718, ???, ???
192 021
If you look at it as two-digit numbers you'll see:10 11 12 13 14 15 16 17 18 19 20 21
#132 - Maths Handshake Puzzle
At a party, everyone shook hands with everybody else. There were 66 handshakes. How many people were at the party?
12
In general, with n+1 people, the number of handshakes is the sum of the first n consecutive numbers: 1+2+3+ ... + n.
Since this sum is n(n+1)/2, we need to solve the equation n(n+1)/2 = 66.
This is the quadratic equation n2+ n -132 = 0. Solving for n, we obtain 11 as the answer and deduce that there were 12 people at the party.
Since 66 is a relatively small number, you can also solve this problem with a hand calculator. Add 1 + 2 = + 3 = +... etc. until the total is 66. The last number that you entered (11) is n.
#133 - Thinking Puzzle
You are driving down the road in your car on a wild, stormy night, when you pass by a bus stop and you see three people waiting for the bus
An old lady who looks as if she is about to die.
An old friend who once saved your life.
The perfect partner you have been dreaming about.
Knowing that there can only be one passenger in your car, whom would you choose?
The old lady of course! After helping the old lady into the car, you can give your keys to your friend, and wait with your perfect partner for the bus
#134 - Tricky Equation Puzzle
Can you arrange four 9's and use of atmost 2 math symbols , make the total be 100?
99 / .99
#135 - King Gift Puzzle
King Charles want to send the diamond ring to his girlfriend securely.He got multiple locks and their corresponding keys.His girl friend does not have any keys to these locks and if he send the key without a lock , the key can be copied in the way.How can charles send the ring to his girl friend securely .
charles put the ring into the box, secure it with one of your locks, and send the box to the girl firend.
She should then attach one of his own locks and return it. When you receive it again, remove your lock and send it back with her lock. Now she can unlock his own lock and retrieve the object.
#136 - Identify The Word Puzzle
The first two letters of an English word refer to a man, the first three refer to a woman, the first four to a great man and the whole word to a great woman. What is the word?
Heroine
#137 - Missing Letter Sequence Puzzle
Can you find the missing letter in the sequence ?
S - T - I - L - ? - T - F - Y - C
The answer is M.
These are letter of the question asked in reverse order.
#138 - Hard Number Series Problem
Can you find the next number in the below sequence
3 , 7 , 10 , 11 , 12 , 17 ?
20(Twenty) : when you write them , these are only numbers having vowel 'E'
#139 - Maths Classic Race Puzzle
Lavesh, Bolt, and Lewis race each other in a 100 meters race. All of them run at a constant speed throughout the race.
Lavesh beats Bolt by 20 meters.
Bolt beats Lewis by 20 meters.
How many meters does Lavesh beat Lewis by ?
Lavesh beats Lewis by 36 meters.
It is tempting to guess that Lavesh beats Lewis by 40 meters, but when Lavesh finishes and is 20 meters ahead of Bolt, Bolt is NOT 20 meters ahead of Lewis (he's only 16 meters ahead), and it will take a couple more seconds before Bolt increases his lead over Lewis to 20 meters.
To figure out the answer, we let Lavesh's speed be A meter/second. So it takes him 100/A seconds to finish the race. At this point, we know that Bolt has run 80 meters (since Lavesh beats him by 20 meters). So Bolt runs 80 meters in 100/A seconds, meaning that he is running at a speed of (80/(100/A)) meters/second, or (8A/10) meters per second.
So we then know that it takes Bolt 100/(8A/10) seconds to finish the race, or 125/A seconds. At this point, we know that Lewis has run 80 meters (since Bolt beats him by 20 meters). So Lewis runs 80 meters in 125/A seconds, meaning that he is running at a speed of (80/(125/A)) meters/second, or 80A/125 meters per second.
Now that we know Lewis's speed, we just need to figure out how far he had run when Lavesh finished the race. Since Lavesh finished in 100/A seconds, we can determine that Lewis had run (100/A) * (80A/125) = 8000/125 = 64 meters when Lavesh finished the race. And so Lavesh beat him by (100 - 64) = 36 meters.
#140 - Logic Puzzle Problem
Like an usual car, my new i10 car has 5 wheels(2 front + 2 Rear + 1 spare).
The rear wheel of the car will wear out after 21000 kilometers and the front wheel will wear out after 29000 kilometers.
What is the maximum distance I can cover assuming changing of wheels is not an issue?
Maximum distance: 30,450 kilometers.
For every 5 kilometers driven using this rotation, each tire will lose (2/29000)+(2/21000) of its tread.So, suppose we drive 5*N kilometers like this. Then, each tire will lose 2*N*((1/29000)+(1/21000)) of its tread. We wish to determine N so that the latter expression gets to be 1, representing all of each tire's tread. That happens when N=6090, which is when 5*N (the total kilometers were driven) is 30,450.