Vancouver is a city on the north bank of the Columbia River in the U.S. state of Washington and the county seat of Clark County.
The width of the twin quilt is 66 +12 (for the two extra columns of 9 patches) + 4 (for the two extra strips of sashing) =82, which is a bit wider than your target of 78, but close enough. Plus, it's nice to have it a bit too large than a bit too small.
Twin Size Mattresses. Twin Mattress Dimensions are 39 x 75. The twin mattress is the most common size found in children's rooms, and has the perfect dimensions to be used on daybeds, trundle units and hideaways. The width of a twin mattress (39) is the minimal amount of space needed for a single person to lie comfortably each night.