What number comes next in this sequence:
12 13 15 17 111 113 117 119 123 ==?==
[Ref: ZBLZ] © Kevin Stone
Hint: You can ignore the first digit.
These are the first 10 prime numbers (2, 3, 5...) prefixed with a 1.
You have the misfortune to own an unreliable clock. This one gains exactly 12 minutes every hour.
It is now showing 10pm and you know that is was correct at midnight, when you set it.
The clock stopped four hours ago, what is the correct time now?
[Ref: ZZXT] © Kevin Stone
Hint: How many clock-minutes pass for each real hour?
Since the clock is gaining 12 minutes every hour, for every real hour that has passed, the clock will show 72 minutes.
Since the clock shows 10.00pm, we know that 22 x 60 = 1320 clock minutes have passed. 1320 ÷ 72 x 60 = 1100.
This therefore equals 1100 real minutes and hence 18 hours 20 minutes = 6:20pm.
The clock stopped 4 hours ago, therefore the time must now be 10.20pm. QED.
What is represented by this BrainBat?
erutuf eht ot
[Ref: ZQXE] Copyrighted.
Answer: Back to the future.
The map below shows the street locations of a city. Position three police officers such that the entire length of every street can be seen by at least one officer.
[Ref: ZMUA] © Cihan Altay Website: otuzoyun.com/pqrst.
Hint: There is an officer at B.
Answer: Position officers at B, G and H.
Using the BrainTracker grid below, how many words can you find? Each word must contain the central
B and no letter can be used twice, however, the letters do not have to be connected. Proper nouns are not allowed, however, plurals are. Can you find the nine letter word?
Excellent: 40 words. Good: 31 words. Average: 25 words.
[Ref: ZGQL] © Kevin Stone
Hint: Every word must contain the central letter.
abet, abort, aerobe, amber, bar, bare, barer, BAROMETER, barter, bat, bate, be, beam, bear, bearer, beat, beater, bee, beet, berate, beret, bet, beta, boa, boar, boat, boater, bore, borer, brat, ember, mob, orb, rebate, rob, robe, tab, tomb.
ab, abet, abort, aborter, aerobe, ambeer, amber, ambo, arb, arbor, ba, bam, bar, bare, barer, barm, BAROMETER, barre, barret, barter, bat, bate, be, beam, bear, bearer, beat, beater, bee, beet, bema, berate, beret, berm, berme, bet, beta, bo, boa, boar, boart, boat, boater, bora, borate, bore, borer, bort, bot, bota, brae, brat, bream, bree, bro, bromate, brome, brr, embar, ember, mabe, mob, obe, omber, ombre, orb, reb, rebar, rebate, rebater, rebato, rebore, rob, robe, tab, taber, tabor, taborer, tomb.