80km/hは何mphですか？
80km/h = 49.71mph
49.71mphを50mphに丸めると0.583%ずれます。この値では小数を残したほうが安全です。
逆に80mphは何km/hですか？
80mph = 128.75km/h
計算式: mph = km/h × 0.621371
km/h → mph 前後の値
35 km/h21.75mph
40 km/h24.85mph
45 km/h27.96mph
50 km/h31.07mph
55 km/h34.18mph
60 km/h37.28mph
65 km/h40.39mph
70 km/h43.5mph
75 km/h46.6mph
80 km/h49.71mph
85 km/h52.82mph
90 km/h55.92mph
95 km/h59.03mph
100 km/h62.14mph
105 km/h65.24mph
110 km/h68.35mph
115 km/h71.46mph
120 km/h74.56mph
125 km/h77.67mph
130 km/h80.78mph