2intersecting lines are shown. a line with points t, r, w intersects a line with points s, r, v at point r. 4 angles are created. clockwise, from the top, the angles are blank, (3 x) degrees, blank, (x + 40) degrees. what is the value of x?

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is