3)8×(1/4p-5/24q+7/12t)= 4)1 3/4×(4a+16/21b-2 2/3)=

3) 8 * (1/4p - 5/24q + 7/12t) = 8 * 1/4p - 8 * 5/24q + 8 * 7/12t = 8/4p - 40/24q + 56/12t = 2p - - 5/3q + 14/3t$4) 1 3/4 * (4a + 16/21b - 2 2/3) = (4 * 1 + 3 / 4) * (4a + 16/21b - (3 * 2 + 2 / 3)) = 7/4 * (4a ++ 16/21b - 8/3) = 7/4 * 4a + 7/4 * 16/21b - 7/4 * 8/3 = 7a + 4/3b - 14/3 = 7a + 1 1/3b - 4 2/3.