I noticed the deliberate mistake included in your quiz.

The answer should be: find plan length of hip = square root of [(6/2)^2 + (6/2)^2] = 4.243; find total rise from eaves to ridge = (6/2) x tan 30° = 1.732; find length of hip = square root of [(4.243^2)+(1.732^2] = 4.582; answer = 4.582 m not 3.46 m.

Even this doesn't take into account the particular arrangement of intersections at hip/ridge and hip/wallplate.

Allan Mountford, Allan F Mountford & Associates, Stoke-on-Trent

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