Question

3.89减去二分之一再减去一又二分之一再减去二分之二等于多少？

Answer 1

原式=3.89 - 0.5 - 1.5 - 1
=3.89 - (0.5+1.5+1)
=3.89 - 3
=0.89

Answer 2

3.89-1/2-1.5-1
=3.89-0.5-1.5-1
=3.89-3
=0.89

Answer 3

＝3.89-0.5-1.5-1＝0.89