4.
-3/4 - 2/3 ÷ (-4/5)
= -3/4 - [2/3 ÷ (-4/5)]
{switch the numerator and denominator when changing from ÷ to ×, or × to ÷}
= -3/4 - [2/3 × (-5/4)]
{numerator × numerator, and denominator × denominator}
= -3/4 - [-10/12]
= -3/4 + 10/12
= -9/12 + 10/12
= 1/12
5.
-2 2/5 + (-2 4/5) × 4/7
= -2 2/5 - (2 4/5 × 4/7)
= -12/5 - (14/5 × 4/7)
= -12/5 - (56/35)
{Simplify fraction to make denominators same}
= -12/5 - (8/5)
= -20/5
= -4/1
= -4
6.
-(-3/5) - 1 3/7 ÷ (-5/14)
{Negative signs cancelled out, fractions compounded}
= 3/5 - 10/7 ÷ (-5/14)
{Switch numerator and denominator when switch from ÷ to ×}
= 3/5 - [10/7 × (-14/5)]
= 3/5 - [-140/35]
= 3/5 + 20/5
= 23/5
{Simplify fraction}
= 4 3/5
Hope this helps! :) You may ask me for more help if you need