Question

Point B ∈ AC so that AB : BC = 2:1. Point D ∈ AB so that AD : DB = 3:2. Find AD : DC.

Answer 1

Answer:

AD :  DC is 2:3

Step-by-step explanation:

The parameters given are;

Point B ∈ AC

AB : BC = 2:1

Point D ∈ AB

AD : DB = 3:2

Therefore, whereby we sum the ratios, we have;

For AC

AB = 2/(2+1)×AC = 2/3×AC

BC = 1/3×AC

For AB

AD = 3/(3+2)×AB = 3/5×AB

DB = 2/5×AB

We are required to find AD:DC

Given that AD = 3/5×AB and AB =  2/3×AC

We have;

AD = 3/5×2/3×AC = 6/15 AC

DC = DB + BC =  2/5×AB + 1/3×AC = 2/5×2/3×AC + 1/3×AC = 4/15×AC + 1/3×AC

DC = 3/5×AC

AD :  DC = 6/15 AC : 3/5×AC = 2:3.