a) $$900 \cdot (148 + 752) - 7 \cdot 6730 + 5878$$
1. $$148 + 752 = 900$$
2. $$900 \cdot 900 = 810000$$
3. $$7 \cdot 6730 = 47110$$
4. $$810000 - 47110 = 762890$$
5. $$762890 + 5878 = 768768$$
Ответ: 768768
b) $$52060 - 340 \cdot 5 + 24160 : (120 : 30) - 44055$$
1. $$120 : 30 = 4$$
2. $$340 \cdot 5 = 1700$$
3. $$24160 : 4 = 6040$$
4. $$52060 - 1700 = 50360$$
5. $$50360 + 6040 = 56400$$
6. $$56400 - 44055 = 12345$$
Ответ: 12345