If a:b=2:5, b:c=3:7 and c:d=1:3 find a:b:c:d?  Options:  A) 6:15:25:115  B) 6:15:35:115  C) 6:15:35:105  D) 6:15:35:125  E) None of these
Explanation:   a:b = 2:5, b:c = 3:7, c:d = 1:3   2:5   3:7   ( a = 2 × 3 = 6, b = 5 × 3 = 15 and c = 5 × 7 = 35)   (a = a × b, b= b × b and c= b × c)   a:b:c = 6 : 15 : 35   a:b:c = 6 : 15 : 35 and c:d = 1 : 3   (Note: First a,b,c multiplication with c means 1 and last c means 35   multiplication with d means 3   a:b:c:d = 6:15:35:105   Answer: Option 6:15:35:105
<result>C</result>
If a:b=2:5, b:c=3:7 and c:d=1:3 find a:b:c:d?