а)( 1 - 3/4)* ( 4/5 - 3/4) б) 1/6 * 2/5 + 3/5 * 1/9  в)14 * ( 1/2 + 1/3 + 3/4)   г) 1/3 * 6/7 -1/7 * 3/4 . памагите поже.

а/ (1 - 3/4)* ( 4/5 - 3/4) = 1/4* 3/5 = 3/20б) 1/6 * 2/5 + 3/5 * 1/9  = 1/15+1/15 =2/15в)14 * ( 1/2 + 1/3 + 3/4)   = 14/1*19/12=226/12=22 1/6г) 1/3 * 6/7 -1/7 * 3/4  =2/7 - 3/28= 5/28