Three Circles Are to Be Bored in a Plate $A$ With a Diameter

Short Answer

Three circles are to be bored in a plate. The circle $A$ with a diameter $4.00 \mathrm{~cm}$ and the circle $B$ with a diameter $5.50 \mathrm{~cm}$ are tangent to the circle $C$ with a diameter $7.50 \mathrm{~cm}$ . Determine the distance between the centre of circle $\mathrm{A}$ and the centre of circle $\mathrm{B}$ .