Question

a:b:c=5:6:7如果a=1/5那么b=多少？c=多少？如果abc都增加2，那么a:b:c=():():()

要有解题思路

Answer 1

(1) 因a:b:c=5:6:7 所以a:b=5:6,而a=1/5,代入可得b=6/25, 因a:c=5:7,再将a=1/5代入,c=7/25. (2)a,b,c 都增加2,则a=2+1/5=11/5,b=6/25+2=56/25,c=7/25+2=57/25. a:b:c=11/5:56/25:57/25=55:56:57.