小学四年级84乘以25应怎样估算 小学生四年级数学25+16➗3是怎么算？
\u5c0f\u5b66\u6570\u5b66\u56db\u5e74\u7ea7\u666e\u901a\u7684\u8ba1\u7b97\u9898\u5c0f\u5b66\u6570\u5b66\u56db\u5e74\u7ea7\u8ba1\u7b97\u9898\u8fc7\u5173\u7ec3\u4e60\u4e8c
1\u3001\u53e3\u7b97(12\u5206)
1.3\uff0d0.8= 630\u00f790= 6\uff0d0.37= 0\u00d7100+100=
60\u00d70= 2.73\uff0b0.27= 0.75\uff0b0.3= 5\u00d79\uff0b1=
4.3\u00f71000= 0.69\uff0b1.1= 300\u00d718= 7\uff0b7\u00d79=
2\u3001\u8ba1\u7b97\u4e0b\u9762\u5404\u9898\uff0c\u80fd\u7b80\u4fbf\u7684\u8981\u7b80\u7b97\u3002(54\u5206)
49\u00d7102\uff0d2\u00d749 125\u00d778\u00d78 8.33\uff0d2.43\uff0d4.57
99\u00d737 6.7-2.63\uff0b3.3-3.37 41000\u00f7\uff0841\u00d75\uff09
3.5\u00d772+6.5\u00d728 5824\u00f78\u00d7\uff0885\uff0d78\uff09 840\u00f728\uff0b70\u00d718
3\u3001\u6839\u636e\u8981\u6c42\u7ed9\u4e0b\u9762\u7b97\u5f0f\u6dfb\u62ec\u53f7\u3002\uff0818\u5206\uff09
\uff081\uff0972+360\u00f79-5 \uff082\uff0972-4\u00d76\u00f73
\u2460\u5148\u7b97\u51cf\u6cd5\uff0c\u518d\u7b97\u9664\u6cd5\uff0c\u6700\u540e\u7b97\u52a0 \u2460\u5148\u7b97\u51cf\u6cd5\uff0c\u518d\u7b97\u4e58\u6cd5\uff0c\u6700\u540e\u7b97\u9664\u6cd5
\u2461\u5148\u7b97\u51cf\u6cd5\u548c\u52a0\u6cd5\uff0c\u6700\u540e\u518d\u7b97\u9664\u6cd5 \u2461\u5148\u7b97\u51cf\u6cd5\u548c\u9664\u6cd5\uff0c\u6700\u540e\u7b97\u4e58\u6cd5
\u2462\u5148\u7b97\u9664\u6cd5\uff0c\u518d\u7b97\u51cf\u6cd5\uff0c\u6700\u540e\u7b97\u52a0\u6cd5 \u2462\u5148\u7b97\u4e58\u6cd5\uff0c\u518d\u7b97\u51cf\u6cd5\uff0c\u6700\u540e\u7b97\u9664\u6cd5
\u5c0f\u5b66\u6570\u5b66\u56db\u5e74\u7ea7\u8ba1\u7b97\u9898\u8fc7\u5173\u7ec3\u4e60\u4e09
1\uff0e\u53e3\u7b97\uff1a(20\u5206)
25\u00d74\uff1d 84\u00f74\uff1d 3\uff0d1.4\uff1d 13\u00f7100\uff1d 120\u00d76\uff1d
85\uff0d58\uff1d 2.5\uff0b0.05\uff1d 45\u00d720\uff1d 100\u00d72.8\uff1d 8\u00d79\uff0b8\uff1d
7\u00d75\u00f77\u00d75\uff1d 125\u00d77\u00d78\uff1d 10\u2015\uff082.3+2.7\uff09\uff1d 7\u00d799\uff0b7= 0.5+1.5=
120\u00f76\u00f72= 4\u00d7\uff0836\uff0d25\uff09= 0.5+0.5= 0.5-0.5= 300\uff0d84\uff0d16=
2\uff0e\u7528\u7ad6\u5f0f\u8ba1\u7b97\u4e0b\u9762\u5404\u9898\u5e76\u9a8c\u7b97\u3002\uff0816\u5206\uff09
10\uff0d3.06 11.36\uff0b8.54
3\uff0e\u8ba1\u7b97\u4e0b\u9762\u5404\u9898\uff0c\u80fd\u7b80\u7b97\u7684\u8981\u7b80\u7b97\u3002\uff0854\u5206\uff09
6.45\uff0d0.58\uff0d1.42 3.27\uff0b6.4\uff0b2.73\uff0b4.6 12000\u00f7125\u00d78
25\u00d744 125\u00d732\u00d725 \uff08160+880\uff09\u00d720
99\u00d745 102\u00d736 12\u00d7\uff08324\uff0d285\uff09\u00f726
\u5c0f\u5b66\u6570\u5b66\u56db\u5e74\u7ea7\u8ba1\u7b97\u9898\u8fc7\u5173\u7ec3\u4e60\u56db
1\u3001\u247436\u52a0\u4e0a36\u9664720\u7684\u5546\uff0c\u518d\u51cf\u53bb6\uff0c\u5dee\u662f\u591a\u5c11\uff1f
\u247536\u52a0\u4e0a720\u9664\u4ee536\u7684\u5546\uff0c\u518d\u51cf\u53bb6\u7684\u5dee\uff0c\u548c\u662f\u591a\u5c11\uff1f
\u247636\u52a0\u4e0a720\u9664\u4ee536\u7684\u5546\uff0c\u518d\u51cf\u53bb6\uff0c\u5546\u662f\u591a\u5c11\uff1f
2\u3001\u247472\u51cf\u53bb4\u4e586\u7684\u79ef\uff0c\u518d\u9664\u4ee53\uff0c\u5dee\u662f\u591a\u5c11\uff1f
\u247572\u51cf\u53bb4\u7684\u5dee\u4e58\u4ee56\uff0c\u518d\u9664\u4ee53\uff0c\u5546\u662f\u591a\u5c11\uff1f
\u247672\u51cf\u53bb4\u7684\u5dee\u4e58\u4ee56\u4e0e3\u7684\u5546\uff0c\u79ef\u662f\u591a\u5c11\uff1f
3\u3001\u2474558\u52a0\u4e0a230\u4e58\u4ee562\uff0c\u518d\u9664\u4ee531\u7684\u5546\uff0c\u548c\u662f\u591a\u5c11\uff1f
\u2475558\u4e0e230\u7684\u548c\u4e58\u4ee562\u4e0e31\u7684\u5546\uff0c\u79ef\u662f\u591a\u5c11\uff1f
\u2476558\u52a0\u4e0a230\u4e0e62\u7684\u79ef\uff0c\u518d\u9664\u4ee531\uff0c\u5546\u662f\u591a\u5c11\uff1f
4\u3001\u247459\u52a0\u4e0a21\u4e58\u4ee596\uff0c\u518d\u9664\u4ee58\uff0c\u548c\u662f\u591a\u5c11\uff1f
\u247559\u4e0e21\u7684\u548c\u4e58\u4ee58\u966496\u7684\u5546\uff0c\u79ef\u662f\u591a\u5c11\uff1f
\u247659\u4e0e21\u548c\u4e58\u4ee596\uff0c\u518d\u9664\u4ee58\uff0c\u5546\u662f\u591a\u5c11\uff1f
\u5c0f\u5b66\u6570\u5b66\u56db\u5e74\u7ea7\u8ba1\u7b97\u9898\u8fc7\u5173\u7ec3\u4e60\u4e94
1\u3001\u6839\u636e\u8fd0\u7b97\u987a\u5e8f\u6dfb\u4e0a\u5c0f\u62ec\u53f7\u6216\u4e2d\u62ec\u53f7\uff1a
(1) 32\u00d7800\uff0d400\u00f725 \u5148\u51cf\u518d\u4e58\u6700\u540e\u9664
(2) 32\u00d7800\uff0d400\u00f725 \u5148\u9664\u518d\u51cf\u6700\u540e\u4e58
(3) 32\u00d7800\uff0d400\u00f725 \u5148\u51cf\u518d\u9664\u6700\u540e\u4e58
2\u3001\u9012\u7b49\u5f0f\u8ba1\u7b97\uff1a
2400\u00f780\uff0d14\u00d72 108\uff0d\uff0883\uff0b360\u00f760\uff09 \uff08420\uff0b48\uff09\u00f7\uff08375\uff0d345\uff09
420\u00f7\uff08205\uff0d198\uff09\u00d74 460\u00f7\uff0829\uff0d18\u00f73\uff09 1450\u00f72\u00d7\uff0816\uff0b9\uff09
3\u3001\u600e\u6837\u7b97\u7b80\u4fbf\u5c31\u600e\u6837\u7b97\uff1a
715+265+335+285 125\u00d732\u00d75 46\u00d7201
7100-137-263+300 75\u00d74\u00d72\u00d75 99\u00d764\uff0b64
3\u3001\u5217\u5f0f\u8ba1\u7b97\uff1a
\uff081\uff0925\u548c40\u7684\u79ef\u662f163\u4e0e87\u7684\u548c\u7684\u591a\u5c11\u500d\uff1f
\uff082\uff09\u4e00\u4e2a\u6570\u76848\u500d\u6bd454\u591a10\uff0c\u8fd9\u4e2a\u6570\u662f\u591a\u5c11\uff1f
\u5b66\u6570\u5b66\u56db\u5e74\u7ea7\u8ba1\u7b97\u9898\u8fc7\u5173\u7ec3\u4e60\u516d
\u4e00\u3001\u76f4\u63a5\u5199\u5f97\u6570\uff1a
400\u00f750= 99\u00f733= 18\u00d750= 470+70=
14\u00d74= 750\u00f750= 1400\u00f770= 6\u00d7120=
480\u00f740= 620-30= 217-65-35= 30-30\u00f75
12\u00d76+8= 5\u00d74\u00d76= 84\u00f74\u00f77= 36\u00f79\u00d75=
\u4e8c\u3001\u7ad6\u5f0f\u8ba1\u7b97\uff1a
996\u00f7 83= 580 \u00f718= 4140 \u00f740=
\u4e09\u3001\u7528\u9012\u7b49\u5f0f\u8ba1\u7b97\u3002
490\u00f770\u00d7154 774\u00f7\uff0817+26\uff09 47\uff0d28\uff0b33
320-770\u00f711\u00d73 960\u00f732\uff0b15\u00d711 451-\uff08164-88\uff09\u00f73
\u56db\u3001\u7b80\u4fbf\u8ba1\u7b97\uff1a
34\uff0b346\uff0b66 74\uff0b\uff08167\uff0b26\uff09 37-56+73-44
25\u00d736 45\u00d7108 248\uff0b302 67\u00d712\u00d75
\u5c0f\u5b66\u6570\u5b66\u56db\u5e74\u7ea7\u8ba1\u7b97\u9898\u8fc7\u5173\u7ec3\u4e60\u4e03
\u4e00\u3001\u53e3\u7b97\uff1a
60\u00d79= 50\u00d790= 600\u00f730= 20\u00d734=
43\u00d72= 11\u00d7600= 13\u00d7600= 75-18=
70-30= 8000-3000= 120\u00f73= 3\u00d7900=
900\u00f73= 320\u00f73= 210\u00d74= 25\u00d7100=
\u4e8c\u3001\u7528\u7ad6\u5f0f\u8ba1\u7b97\uff1a
38\u00d7250\uff1d\u3000\u3000\u3000\u3000\u3000\u30007580\u00f754\uff1d\u3000\u3000\u3000\u3000\u3000\u3000140\u00d7250\uff1d
508\u00d715\uff1d\u3000\u3000\u3000\u3000 \u30008500\u00f770\uff1d\u3000\u3000\u3000\u3000\u3000\u300040800\u00f7340\uff1d
\u4e09\u3001\u7b80\u4fbf\u8ba1\u7b97\uff1a
55\u00d722\uff0b78\u00d7 55 203\u00d746 203\u00d746-3\u00d746
99\u00d778 49\u00d799\uff0b99 98\u00d7101 98\u00d7101\uff0d98
49\u00d799+49 45\uff0b45\u00d726\uff0b45\u00d773 38\u00d736\uff0d36\u00d78
125\u00d732\u00d725 43\uff0b57\uff0d43\uff0b57 24\u00d75\uff0d24\u00d75
24\u00d75\u00f724\u00d75 576\uff0d203 289\uff0b104
\u5c0f\u5b66\u6570\u5b66\u56db\u5e74\u7ea7\u8ba1\u7b97\u9898\u8fc7\u5173\u7ec3\u4e60\u516b
1\u3001\u76f4\u63a5\u5199\u5f97\u6570\u3002
62\u00d73\uff1d 0\u00d765+5\uff1d 77\u00d720\uff1d 6+18+84\uff1d
98+12\uff1d 42\u00d71\u00d75\uff1d 12\u00d725\uff1d 9\u00d75\u00f75\u00d79\uff1d
460\uff0b280\uff1d\u3000\u3000810\u00f727\uff1d\u3000\u3000 \u3000540\u00f7270\uff1d\u3000 \u3000240\u00d730\uff1d
2\u3001\u8ba1\u7b97\u4e0b\u9762\u5404\u9898\u3002\uff08\u80fd\u7b80\u7b97\u7684\u8981\u7b80\u7b97\uff09
874\u00f7\uff0824\u00d723\uff0d506\uff09 25\u00d75\u00f7\uff08155\uff0d30\uff09 25\u00d799
25\u00d7\uff08696\uff0b456\uff09\u00f716 \u3000\u3000 48\u00d7\uff0839\uff0d594\u00f733\uff09 \uff0840+4\uff09\u00d725
96\u00d7101\uff0d96 486\uff0d\uff08186\uff0b59\uff09\uff0d41 863\uff0d297
3\u3001\u5217\u7efc\u5408\u7b97\u5f0f\u8ba1\u7b97\u3002
\uff081\uff09 45\u4e5845\u51cf\u53bb27\u7684\u5dee\uff0c\u79ef\u662f\u591a\u5c11\uff1f
\uff082\uff0956\u52a0\u4e0a48\u4e583\u7684\u79ef\uff0c\u548c\u662f\u591a\u5c11\uff1f
\uff083\uff09288\u9664\u4ee518\u4e584\u7684\u79ef\uff0c\u5546\u662f\u591a\u5c11\uff1f
\u5c0f\u5b66\u6570\u5b66\u56db\u5e74\u7ea7\u8ba1\u7b97\u9898\u8fc7\u5173\u7ec3\u4e60\u4e5d
\u4e00\u3001\u7528\u7ad6\u5f0f\u8ba1\u7b97\uff0c\u5e26\u203b\u7684\u8981\u9a8c\u7b97\u3002
\u203b215\u00f724\uff1d\u3000\u3000\u3000\u3000\u3000\u3000\u3000\u3000900\u00f724\uff1d\u3000\u3000\u3000\u3000\u3000\u3000\u3000\u3000\u3000\u3000\u203b56\u00d735\uff1d
\u4e8c\u3001\u8131\u5f0f\u8ba1\u7b97\u3002
175\uff0d75\u00f725\u3000\u3000\u3000\u3000\u300068\uff0b35\u00d713\u3000\u3000\u3000\u3000\u3000\u3000\u3000\u3000725\uff0d\uff08125\uff0b237\uff09
\uff08114\uff0b166\uff09\u00f735\u3000\u3000\u3000\u3000\u3000432\u00f7\uff089\u00d78\uff09\u3000\u3000\u3000\u3000189\uff0d60\uff0b40
\u4e09\u3001\u7b80\u4fbf\u8ba1\u7b97\u3002
216\uff0b305\u3000\u3000\u3000\u3000\u3000\u3000\u300025\u00d732\u3000\u3000\u3000\u3000\u3000\u3000\u3000 \u3000\u300047\uff0b236\uff0b64
6\u00d7\uff0815\u00d79\uff09\u3000\u3000\u3000\u3000\u3000\u3000402\uff0b359\u3000\u3000\u3000\u3000\u3000\u3000\u3000\u3000\u300043\uff0b78\uff0b122\uff0b257
25\u00d7\uff0826\u00d74\uff09\u3000\u3000\u3000\u3000\u300025\u00d744\u3000\u3000\u3000\u3000\u3000\u3000\u3000 \u3000\u3000354\uff0b\uff08229\uff0b46\uff09
2\u3001\u5c0f\u7075\u5728\u8ba1\u7b97\u9664\u6cd5\u65f6\uff0c\u628a\u9664\u657041\u9519\u5199\u4e8614\uff0c\u7ed3\u679c\u5f97\u5230\u7684\u5546\u662f28\u8fd8\u4f598\uff0c\u4f60\u80fd\u7b97\u51fa\u5b83\u7684\u6b63\u786e\u7ed3\u679c\u5417?
\u8fd9\u9053\u9898\u51fa\u5f97\u6709\u95ee\u9898\uff0c\u5728\u8131\u5f0f\u8ba1\u7b97\u8fc7\u7a0b\u4e2d\u4e00\u822c\u4e0d\u51fa\u73b0\u9664\u4e0d\u5c3d(16\u00f73)\u8fd9\u6837\u7684\u60c5\u51b5\uff0c\u51fa\u73b0\u8fd9\u79cd\u60c5\u51b5\uff0c\u5bf9\u5b66\u751f\u6765\u8bf4\u53ef\u4e0d\u505a\u3002
84*25=84/2/2*100，按此估算最快这道题不需要估算，可以精确地计算
84*25=80*25+4*25=2000+100=2100
因为本题的两个数不接近整十数，估算出来的数相误错是很大的
但可以这样估算
80*30=2400
90*20=1800
在1800到2400之间。一大一小来估算。
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绛旓細350X42=700X21=14700 姣14700澶氫竴浜涖
绛旓細鍦ㄤ笁骞寸骇鏁板涓婂唽锛屾湁銆婂厠銆佸崈鍏嬨佸惃鐨勮璇嗐嬨併婁袱涓変綅鏁伴櫎浠ヤ竴浣嶆暟銆嬨併婁袱浣嶆暟涔樹袱浣嶆暟銆嬪強銆婇暱鏂瑰舰鍜屾鏂瑰舰鐨勯潰绉嬶紝杩欏洓涓崟鍏冮兘瑕佺敤浼扮畻鏉ヨ緟鍔╁鐢熷鐭ヨ瘑鐨勭悊瑙ｅ拰娓楅忋傛墍浠ュ湪鏁欏涓紝缁忓父娓楅忎及绠楁濇兂绮惧績璁捐闂锛屾縺鍙戝鐢熸濊冿紝寮曞瀛︾敓瀛︿細浼扮畻銆傛垜鍦ㄦ暀闈㈢Н鏃讹紝鍏堝嚭绀哄噯澶囬锛氬湪涓嬪垪锛 ...
绛旓細132x49鈮130x50=6500 鏈嬪弸锛岃銆愰噰绾崇瓟妗堛戯紝鎮ㄧ殑閲囩撼鏄垜绛旈鐨勫姩鍔涳紝璋㈣阿銆
绛旓細鎴戣灏忓鍥涘勾绾鏁板棰,涓嶈鏄:瀛︽牎鍑嗗鍙戠粌涔犳湰,鍙戠粰15涓彮,姣忕彮144鏈,杩樿鐣40鏈綔涓哄鐢ㄣ傚鏍″簲涔板灏戠粌涔犳湰?杩欐牱鏃犺亰鐨勯棶棰,瑕佸皬瀛﹀洓骞寸骇涓嬪唽鏁板棰,鏈夊皬鏁扮殑绉诲姩銆佷箻闄ゆ硶... 鎴戣灏忓鍥涘勾绾ф暟瀛﹂,涓嶈鏄:瀛︽牎鍑嗗鍙戠粌涔犳湰,鍙戠粰15涓彮,姣忕彮144鏈,杩樿鐣40鏈綔涓哄鐢ㄣ傚鏍″簲涔板灏戠粌涔犳湰?杩欐牱鏃犺亰鐨...
绛旓細2銆佸晢涓嶅彉锛氳闄ゆ暟鍜岄櫎鏁板悓鏃涔(鎴栭櫎浠)鐩稿悓鐨勬暟(0闄ゅ)锛屽晢涓嶅彉銆(鍥)绠渚胯绠楋細鍚屾椂鍘绘帀鍚屾牱澶氱殑0锛屽9100梅700=91梅7=13 濡備綍鎻愰珮鍥涘勾绾у皬瀛︾敓鐨勬暟瀛﹀涔犲叴瓒?涓銆佸垱璁炬帰绱㈡ф儏澧冿紝婵鍙戝涔犲叴瓒 鐞嗚鏇炬彁鍑鸿繃鈥滀笁涓烩濈殑瑙傜偣锛氬嵆璇惧爞鏁欏搴斾互瀛︾敓鐨勫彂灞曚负涓荤嚎锛屼互瀛︾敓鎺㈢储鎬х殑瀛︿负涓讳綋锛屼互鏁欏笀...
绛旓細2020灏忓鍥涘勾绾涓婂唽鏁板鐭ヨ瘑鐐瑰綊绾3 绗洓鍗曞厓 銆愪笁浣嶆暟涔樹袱浣嶆暟銆 1銆 涓や綅鏁颁箻涓浣嶆暟鐨勫彛绠涔樻硶:(濡16脳3)鎶16鍒嗘垚10鍜6,鍏堢畻10脳3=30,鍐6脳3=18,鏈鍚庣畻30+18=48,鎵浠16脳3=48銆 2銆 涓変綅鏁(鏈熬鏈0)涔樹竴浣嶆暟鐨勫彛绠椾箻娉:(濡160脳3)鎶婃湯灏0鐨勯儴鍒嗗厛涓嶇湅,鐪嬫垚16脳3,鍙ｇ畻鍑哄緱48,鍐嶅湪寰楁暟鐨...
绛旓細灏忓鍥涘勾绾涓嬪唽鏁板鏈熸湯鑰冭瘯璇曢 5 涓銆佸～绌 1.鐢ㄥ瓧姣嶈〃绀哄姞娉曚氦鎹㈠緥鏄(+=+);鐢ㄥ瓧姣嶈〃绀涔樻硶缁撳悎寰嬫槸()=()銆 2.涓涓暱鏂瑰舰鐨勯暱鏄16鍘樼背,瀹芥槸10鍘樼背,姹傝繖涓暱鏂瑰舰鐨勯潰绉彲浠ュ垪寮忎负(10),杩樺彲浠ュ垪寮忎负(),闈㈢Н閮界瓑浜()骞虫柟鍘樼背銆 3.鍦ㄨ绠32+45+55鏃,鍙互鍔犳硶缁撳悎寰,鍏堢畻(+)銆(鎸夊嚭鐜扮殑鍏堝悗椤哄簭濉啓...
