计算题.2.21,28,33,42,43,60,( ) A.45 B.56 C.75 D.92 这题怎么算啊,
问题描述:
计算题.2.21,28,33,42,43,60,( ) A.45 B.56 C.75 D.92 这题怎么算啊,
计算题.
2.21,28,33,42,43,60,( )
A.45 B.56 C.75 D.92
这题怎么算啊,
答
A.45
21 28 33 42 43 60 ( 45 )
+7 + 5 +9 +1 +17 ( -15)
-2 +4 -8 +16 (-32)