Question

2分之1加负3分之2加5分之4加负2分之1加负3分之1

Answer 1

1/2 + (-2/3) + 4/5 + (-1/2) + (-1/3)
= -2/3 - 1/3 +1/2 -1/2 +4/5
= -1 + 4/5
= - 1/5