一个长方形菜地,长是7米,宽是5米,四周围上篱笆,篱笆长多少?如果菜地有一面靠墙,那么篱笆至少长多 一块长方形菜地,长7米,宽2米.四周围上篱笆,篱笆长多少米?...
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\u6269\u5c55\u8d44\u6599\u6027\u8d28
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\uff086\uff09\u67092\u6761\u5bf9\u79f0\u8f74\uff08\u6b63\u65b9\u5f62\u67094\u6761\uff09\uff1b
\uff087\uff09\u5177\u6709\u4e0d\u7a33\u5b9a\u6027\uff08\u6613\u53d8\u5f62\uff09\u3002
篱笆长27米,如果长靠墙,则17米,如宽靠墙,则19米
篱笆长35米,若靠一面墙篱笆长30或28米。。。
篱笆长24米,至少长17米
1. 5x7=35(米) 2.5x2+7=17(米)
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