Total journey average speed = (total distance travelled ÷ total time taken).Total distance travelled = 213 miles + 37 miles = 250 milesTotal time taken (hours) = 4 + (50÷60) + time from Manchester to Liverpooltime from Liverpool to Manchester (hours) = distance travelled (miles) ÷ speed(mph) = 37 ÷ 90 = 0.411 hoursTotal average journey speed = 250 ÷ (4 + (50÷60) + 0.411) = 47.67 mph