Выполните умножение устно а) 2/5 * 5/8 * 8/11 * 11/14; б) 3/7 * 5/9 * 7/3 * 9/5; в) 3 * 1/3 * 4 * 1/4 * 5 * 1/5 * 6 * 1/6
А) 2/5 * 5/8 = 2/8 * 8/11= 2/11 * 11/14=2/14 б) 3/7 * 5/9 = 5/21 * 7/3 = 5/9 * 9/5 = 1 в) 3 * 1/3 = 1 * 4 = 4 *1/4= 1 *5 = 5 * 1/5 = 1 * 6 = 6 * 1/6 = 1