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0 sats \ 8 replies \ @south_korea_ln 3 Nov \ on: Are you smarter than a 12-year-old? #2 science

I must have made a mistake, because the only way for it to work out is to have a negative length for RS ;)

I'll check again later when i have pen and paper in front of me.

10 sats \ 7 replies \ @south_korea_ln 3 Nov

Oh, my bad. I forgot the overlap between the two top trapezia in Figure 2. My answer in (a) was 42 (@Aardvark~~), instead of 21.

Answers: (a) 21 cm (b) 13 cm

0 sats \ 6 replies \ @Aardvark 3 Nov

Odd, I must be making the exact same mistake.. I've done it several times now and I also keep coming up with 42..... Are you sure it was a mistake?

24 sats \ 5 replies \ @south_korea_ln 3 Nov

Yes, 21 cm is the correct length.

3 times the perimeter of a single trapezoid is 288 cm.

288-204 = 84cm. 84 cm corresponds to 4 times the length of PQ. Twice for the overlap between the top 2 trapezoids in Fig. 2 and twice for the overlap between the top left and the trapezoid just below in the same figure.

84/4=21 cm.

66 sats \ 3 replies \ @Aardvark 3 Nov

Oh, I see where you made the mistake. You did actual math instead of just guessing 42....

Don't worry, it happens to the best of us.

40 sats \ 1 reply \ @south_korea_ln 3 Nov

You got me ;)

0 sats \ 0 replies \ @Aardvark 3 Nov

0 sats \ 0 replies \ @cryotosensei OP 3 Nov

No worries, I will tag you when I have a question that requires 42 as the answer

0 sats \ 0 replies \ @cryotosensei OP 3 Nov

Splendid!

Sensei approves