# Question #3a15a

##### 1 Answer

The centre-of-mass is at a distance of

#### Explanation:

**Total Mass**: We can write the total mass

**Eq 1**)

**Centre-of-Mass**:

If

**Eq 2**)

Substituting for **Eq 1** in **Eq 2**,

Dec 19, 2017

**Total Mass**: We can write the total mass

**Eq 1**)

**Centre-of-Mass**:

If

**Eq 2**)

Substituting for **Eq 1** in **Eq 2**,