1)(-7/18+11/12):(-19/48)=? 2)(7/16-(-5/24)):(-1целая 15/16)=? 3)(10/21-25/28):(-11/14+24/35)=? Помогите

Первый: 1) - 7/18 + 11/12 = - 2*7/36 + 3*11/36 = - 14/36 + 33/36 = 19/36; 2) 19/36 : (-19/48) = 19/36 * (-48/19) = 1/3 * (-4/1) = - 4/3 = - 1 1/3. Ответ: - 1 1/3. Второй: 1) 7/16 - (-5/24) = 7/16 + 5/24 = 3*7/48 + 2*5/48 = 21/48 + 10/48 = 31/48; 2) 31/48 : (-1 15/16) = 31/48 : (-31/16) = 31/48 * (-16/31) = 1/3 * (-1/1) = - 1/3. Ответ: - 1/3. Третий: 1) 10/21 - 25/28 = 4*10/84 - 3*25/84 = 40/84 - 75/84 = - 35/84; 2) - 11/14 + 24/35 = - 5*11/70 + 2*24/70 = - 55/70 + 48/70 = - 7/70 = - 1/10; 3) - 35/84 : (-1/10) = - 35/84 * (-10/1) = - 35/42 * (-5/1) = 175/42 = 4 7/42 = 4 1/6. Ответ: 4 1/6.