0.8×4×1.25×2.5
=(0.8*1.25)*(4*2.5)
=1*10
=10
2.35×7分之5+4.65×7分之5
=7分之5×(2.35+4.65)
=7分之5×7
=5
5.35-13÷2.6
=5.35-5
=0.35