Hint
You might find Pythagoras' theorem very useful [a2 + b2 = c2].
Answer
148 inches.
We can use Pythagoras' theorem if we draw an imaginary line across to create a right-angled triangle.
The hypotenuse is equal to the rope's length R. The bottom of the triangle is 48 inches. The vertical side is R - 8 (the difference between 20 inches and 12 inches).
Pythagoras' theorem tells us that:
a2 + b2 = c2
Where c is the hypotenuse.
This gives us:
482 + (R - 8)2 = R2
2304 + (R - 8)(R - 8) = R2
2304 + R2 - 16R + 64 = R2
2304 - 16R + 64 = 0
16R = 2368
R = 148
As required.
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Puzzle 318
Here is a well known proverb with the consonants removed. What is the proverb.
A -i-- i- --e -a-- i- -o--- --o i- --e -u--.
During the recent BrainBashers school sports day, four students were competing in the 400 metres hurdles.
Official figures mysteriously went missing just after the event, however, various spectators could remember the following information.
Alex won and wore red. The student wearing number 1 came third. Billie beat the student in yellow, but wasn't wearing number 2. Only one student finished in the same position as the number they wore, but they didn't wear red. Emery beat the student wearing number 3, and Glen wore yellow. The student in green wore number 2. A spectator remembered that one student wore blue, but couldn't remember anything else about them.
Can you determine the positions the students finished in, along with the numbers and colours they wore?
Answer # Name Wore Colour
1 Alex 4 Red
2 Emery 2 Green
3 Billie 1 Blue
4 Glen 3 Yellow
Reasoning
(Clue 1) Alex won and wore Red. (Clue 5) Glen wore Yellow. (Clue 3) Billie wasn't wearing number 2, and (Clue 6) number 2 wore Green, so must be Emery. Leaving Billie in Blue. # Name Wore Colour
1 Alex Red
? Glen Yellow
? Emery 2 Green
? Billie Blue
(Clue 2) Emery didn't come 3rd, and Alex won, so (Clue 5) Emery can't have come last, so must have come 2nd. # Name Wore Colour
1 Alex Red
2 Emery 2 Green
? Glen Yellow
? Billie Blue
(Clue 3) Billie can't have been last, so came 3rd and (Clue 2) wore 1, leaving Glen in last place. # Name Wore Colour
1 Alex Red
2 Emery 2 Green
3 Billie 1 Blue
4 Glen Yellow
(Clue 5) Emery beat the student wearing 3, so Glen must have worn 3. Leaving Alex wearing 4. # Name Wore Colour
1 Alex 4 Red
2 Emery 2 Green
3 Billie 1 Blue
4 Glen 3 Yellow
