Simple calculation of 4 + 4 / 5 × (3 / 4 + 8 / 6) - 4 / 5 △ 2 / 9

Simple calculation of 4 + 4 / 5 × (3 / 4 + 8 / 6) - 4 / 5 △ 2 / 9

4+4/5×(3/4+8/6)-4/5÷2/9
=4+4/5×(9/12+16/12)-4/5×9/2
=4+4/5×(25/12-54/12)
=4+4/5×29/12
=4+29/15
=89/15

How to calculate 8 △ 8 [(40.75-9.5) × 0.4] - 0.64

8÷[(40.75-9.5)×0.4]-0.64
=8÷(31.25×0.4)-0.64
=8÷12.5-0.64
=(8×8)÷(8×12.5)-0.64
=64÷100-0.64
=0.64-0.64
=0

8 and 1 / 5-0.6 × (0.9-3 / 4)
A construction site needs 36 tons of concrete, of which 1 / 4 is cement, 7.2 tons is yellow sand, the rest is stone, stone () tons

8 and 1 / 5-0.6 × (0.9-3 / 4)
=8 1 / 5-0.6 × 0.15
=8.2-0.09
=8.01
A construction site needs 36 tons of concrete, of which 1 / 4 is cement, 7.2 tons is yellow sand, the rest is stone, stone () tons
36×（1-1/4）-7.2
=27-7.2
=19.8 tons

8-6 / 9 + 2 / 9 + 5-12 / 9 + 4 / 9

8 / 9-5 / 6 + 2 / 9
=(8 / 9 + 2 / 9) - 5 / 6
=1-5 / 6
=One in six
5 / 9-5 / 12 + 4 / 9
=(5 / 9 + 4 / 9) - 5 / 12
=1-5 / 12
=7 out of 12