38+1-1+2-2+3-3等于多少

---

等于38
38+（1-1）+（2-2）+（3-3）=38

---

38+1-1+2-2+3-3等凯正肢迅于(38)，盯饥悔
38+1-1+2-2+3-3
=38+(1-1)+(2-2)+(3-3)
=38+0+0+0
=38

---

38+1-1+2-2+3-3等于38。

---

等于38

---

1+2+3……37+38+39 =（1+39）+（2+38）+........+（19+21）+20 =7x40+20 =280+20 =300

---