Puzzle 216

How many squares, of any size, can you find on this chess board that do not contain a Rook?

[Ref: ZDPX] © Kevin Stone

Hint: There are no squares of size 5x5.

Answer: 125.
There are 61 squares of size 1x1.
There are 39 squares of size 2x2.
There are 20 squares of size 3x3.
There are 5 squares of size 4x4.
A total of 61 + 39 + 20 + 5.

Puzzle 217

I started a journey to my Aunt's yesterday with a full tank of gasoline, 10 gallons, but at that exact moment my gasoline tank sprang a leak.
I managed to drive 50 miles, exactly one hour, before coming to a complete stop with an empty tank.
I know that the car manages 25 miles per gallon.
How quickly was I losing gasoline?

[Ref: ZRNJ] © Kevin Stone

Hint: How many gallons did the journey use?

Answer: 8 gallons an hour.
Since I was travelled 50 miles in the one hour, this must have used 2 gallons (at 25 miles per gallon).
So I must have lost the other 8 gallons through the hole.

Puzzle 218

What is the sum of all of the numbers from 1 to 1000?

[Ref: ZONR]

Hint: Add the first number to the last - does this help?

Answer: 500,500.
It's easiest to see that the first and last number are 1 and 1000, which add to 1001.
The next two numbers we can add are 2 and 999, which add to 1001.
The next two numbers to add are 3 and 998, which add to 1001.
We can keep doing this 500 times, and in each case they add to 1001.
And 500 x 1001 = 500,500.

Puzzle 219

What is represented by this BrainBat?

SCHEME
SCHEME SCHEME
SCHEME SCHEME SCHEME
SCHEME SCHEME SCHEME SCHEME
SCHEME SCHEME SCHEME SCHEME SCHEME
SCHEME SCHEME SCHEME SCHEME SCHEME SCHEME

[Ref: ZSFS]

Puzzle 220

Using the BrainTracker grid below, how many words can you find? Each word must contain the central G and no letter can be used twice. The letters do not have to be connected. Proper nouns are not allowed, however, plurals are. Can you find the nine letter word?
Excellent: 109 words. Good: 80 words. Average: 50 words.

[Ref: ZEDM] © Kevin Stone

Hint: Every word must contain the central letter.

Answer: Signature.
Common words:
aegis, age, agent, ague, anger, angriest, angst, argent, argue, auger, easing, eating, erasing, gain, gainer, gait, gaiter, gantries, garnet, gas, gate, gaunt, gear, genius, gent, genus, get, giant, girt, gist, gnat, gnu, grain, granite, grant, grate, gratis, great, grin, grist, grit, grunt, guest, guinea, guise, guitar, gun, gust, gut, ingest, nag, rag, rage, rang, range, rating, regain, reign, resign, resting, rig, ring, rug, ruing, rung, rusting, sag, sage, sang, searing, seating, sign, SIGNATURE , signer, signet, sing, singe, singer, snag, snug, stag, stage, stager, staring, sting, stinger, strange, string, strung, stung, sugar, suing, sung, surge, tag, tang, tangier, tearing, teasing, tiger, ting, tinge, tug, urge, urgent, usage, using.
All words:
aegis, ag, age, ageist, agent, agents, ager, agers, ages, agin, agist, ague, agues, aigret, aigrets, anger, angers, angriest, angst, argent, argents, argue, argues, argus, astringe, auger, augers, augite, augites, earing, earings, easing, easting, eating, eatings, egis, eng, engirt, engs, erasing, erg, ergs, gae, gaen, gaes, gain, gainer, gainers, gains, gainst, gait, gaiter, gaiters, gaits, gan, gane, ganister, gantries, gar, garnet, garnets, garni, gars, gas, gast, gaster, gastrin, gat, gate, gates, gats, gaun, gaunt, gaunter, GAUNTRIES , gaur, gaurs, gear, gears, gen, genius, gens, gent, gents, genu, genua, genus, gest, get, geta, getas, gets, giant, giants, gie, gien, gies, girn, girns, girt, girts, gist, gnar, gnars, gnat, gnats, gnu, gnus, grain, grains, gran, granite, granites, grans, grant, grants, grat, grate, grates, gratin, gratine, gratins, gratis, great, greats, grin, grins, grist, grit, grits, grue, grues, grunt, grunts, guan, guans, guar, guars, guest, guinea, guineas, guise, guitar, guitars, gun, gunite, gunites, guns, gurnet, gurnets, gust, gustier, gut, guts, gutsier, ingate, ingates, ingest, ingesta, ingrate, ingrates, nag, nags, negus, rag, rage, rages, ragi, ragis, rags, rang, range, ranges, rangiest, rasing, rating, ratings, reagin, reagins, reg, regain, regains, regina, reginas, regius, regna, regs, reign, reigns, renig, renigs, resign, resting, retag, retags, reusing, rig, rigs, ring, rings, rug, ruga, rugae, rugate, rugs, ruing, rung, rungs, rusting, sag, sage, sager, sagier, sang, sanger, sarge, sating, sauger, sauteing, seagirt, searing, seating, seg, segni, sengi, sering, seringa, sign, SIGNATURE , signer, signet, sing, singe, singer, snag, snug, stag, stage, stager, stagier, staig, stang, staring, sting, stinger, strang, strange, string, strung, stung, sugar, suing, sung, surge, tag, tags, tang, tangier, tangs, targe, targes, taring, tearing, teasing, teg, tegs, tegua, teguas, terga, tiger, tigers, ting, tinge, tinges, tings, tragi, tragus, triage, triages, trig, trigs, trueing, trug, trugs, truing, tug, tugs, tung, tungs, ungirt, unitage, unitages, unrig, unrigs, urge, urgent, urges, usage, using.