图书馆有科技书50本，又新进9本，现在有多少本？3s)I1m'n*o,L3i4h7m
算式：提示9q,X0R9U(g(J/v1Q(H:L2h(Q4R3\;B3s)I1m'n*o,L3i4h7m
答：现在有/L8b.{*v5\7M:N本。3s)I1m'n*o,L3i4h7m