一批钢管叠成一堆,最下层有10根,每上1层少放1根,最上1层放了5根.这批钢管有多少根?0l'h/d0n*|
算式：提示;B+J.b2|5e/R6q(^5T5k'U)_3b8U*M0l'h/d0n*|
答：这批钢管有(s.m7m-a*V-F(M,g;c1M:\6I*O根。0l'h/d0n*|