是4分之一乘(4.85“乘”以18分之5减3.6+6.15乘3又5分之3)吧
=1/4×(4.85×3.6-3.6+6.15×3.6)
=1/4×3.6×(4.85-1+6.15)
=1/4×3.6×10
=9