a)
1. $$6 + 0.3 = 6.3$$
2. $$6.3 : 9 = 0.7$$
3. $$0.7 - 4 = -3.3$$
4. $$-3.3 + 0.8 = -2.5$$
Ответ: -2.5
б)
1. $$11.9 - 2 = 9.9$$
2. $$9.9 : 3 = 3.3$$
3. $$3.3 + 4.7 = 8$$
4. $$8 - 6 = 2$$
Ответ: 2
в)
1. $$6 - 1.2 = 4.8$$
2. $$4.8 : 8 = 0.6$$
3. $$0.6 + 0.6 = 1.2$$
4. $$1.2 : 2 = 0.6$$
Ответ: 0.6
г)
1. $$60 \cdot 0.4 = 24$$
2. $$24 : 10 = 2.4$$
3. $$2.4 + 0.4 = 2.8$$
4. $$2.8 : 4 = 0.7$$
Ответ: 0.7