3,9,27,81(=81*3=243)A.243 B.342 C.433 D.135
3=3^1
9=3^2
27=3^3
81=3^4
243=3^5
8,8,12,24,60(180 )A.90 B.120 C.180 D.240
8/8=1
12/8=1.5
24/12=2
60/24=2.5
x/60=3,则x=180
8,14,26,50(98)A.76 B.98 C.100 D.104
14-8=6
26-14=12
50-26=24
98-50=48
66,83,102,123 (=123+23=146)A.144 B.145 C.146 D.147
83-66=17
102-83=19
123-102=21
146-123=23
4,13,40,121,361(364+243*3=1093)A.1090 B.1094 C.728 D.1093
13-4=9
40-13=27
121-40=81
364-121=243
1093-364=729
93,114,136,159(=159+24=183)A.180 B.183 C.185 D.187
114-93=21
136-114=22
159-136=23
183-159=24
7,19,22,28,37 (37)A.47 B.49 C.51 D.53
解法1 37
奇数位7、22、37 相差15
偶数位19 28 37 相差9
解法2 49
从19位开始
22-19=3
28-22=6
37-28=9
49-37=12
2/3,7/12,11/30,15/56(=(15+4)/(56+34)=19/90)A.17/72 B.19/64 C.19/90 D.23/121
3/2=1+1/2
7/12=1/3+1/4
11/30=1/5+1/6
15/56=1/7+1/8
1/9+1/10=19/90