Two plates are connected by fillet welds of size 10 mm and subjected o tension, as shown in the sketch. The thickness of each plate is 12 mm. The yield stress and ultimate tensile stress of steel are 250 MPa and 410 MPa, respectively. The welding is done in the workshop ($y_{mw}$= 1.25). As per the Limit State Method of IS 800 : 2007, the minimum length (rounded off to the nearest higher multiple of 5 mm) of each weld to transmit a force P equal to 270 kN is