48 * 5 = 48 * 10 : 2 = 480 : 2 = 240,

290 : 5 = 290 : 10 * 2 = 29 * 2 = 58,

670 : 5 = 670 : 10 * 2 = 67 * 2 = 134,

54 * 5 = 54 * 10 : 2 = 540 : 2 = 270,

8 * 50 = 8 * 5 * 10 = 40 * 10 = 400,

900 : 50 = 900 : 100 * 2 = 9 * 2 = 18,

360 : 5 = 360 : 10 * 2 = 36 * 2 = 72,

840 : 5 = 840 : 10 * 2 = 84 * 2 = 168