A.n+1 B.n+2
C.n-1 D.n-2
①-18.52+12.6-1.48
②12.5%×25%×32
③
④1.25×99+
⑤35÷[()×3]
-5 +4.5 -4
(个)
+0.375= 2.5×(17×4)= 631÷89≈
0.32= ×÷×=