题目错了吧,或者你的4.85/5/18 应该是4.85 / (5/18)
应该是
1/4*(4.85/5*18-3.6+6.15*18/5)
= 1/4 * (4.85*18/5 - 18/5 + 6.15*18/5)
= 1/4 * [(4.85 - 1 + 6.15) * 18 / 5]
= 1/4 * (10 * 18 / 5)
= 9
题目错了吧,或者你的4.85/5/18 应该是4.85 / (5/18)
应该是
1/4*(4.85/5*18-3.6+6.15*18/5)
= 1/4 * (4.85*18/5 - 18/5 + 6.15*18/5)
= 1/4 * [(4.85 - 1 + 6.15) * 18 / 5]
= 1/4 * (10 * 18 / 5)
= 9