亚洲激情+欧美激情,无码任你躁久久久久久,我的极品美女老婆,性欧美牲交在线视频,亚洲av高清在线一区二区三区

電子課本網(wǎng) 第62頁(yè)

第62頁(yè)

信息發(fā)布者:
=
=


327 + 91 + 73 = (327 + 73) + 91 = 400 + 91 = 491
98 + (24 + 102) = (98 + 102) + 24 = 200 + 24 = 224
25 + (57 + 175) + 143 = (25 + 175) + (57 + 143) = 200 + 200 = 400
10003 + 1003 + 103 + 13 = (10000 + 3) + (1000 + 3) + (100 + 3) + (10 + 3) = (10000 + 1000 + 100 + 10) + (3 + 3 + 3 + 3) = 11110 + 12 = 11122
800
505
269 + 232 + 168 = 269 + (232 + 168) = 269 + 400 = 669(人)
答:三個(gè)年級(jí)一共去了669人。
400 - 31 - 124 - 45 = 400 - (31 + 124 + 45) = 400 - 200 = 200
47 + 48 + 49 + 50 + 51 + 52 + 53 = (47 + 53) + (48 + 52) + (49 + 51) + 50 = 100 + 100 + 100 + 50 = 350
568 + 236 + 32 = 568 + 32 + 236 = 600 + 236 = 836(棵)
答:果園里有果樹836棵。
加法交換律、加法結(jié)合律
2 + 4 + 6 + ...+ 198 + 200 = (2 + 200) + (4 + 198) + (6 + 196) +...+ (100 + 102) = 202×50 = 10100