Question

Two circles of diameters $10cm$ and $4cm$, touch each other externally. Find the distance between their centres (in $cm$).

Answer 1

$d=10cmd=4cm$
$R=\frac{10}{2}=5cmr=\frac{4}{2}=2cm$
Distance between centres $d=R+r$
$d=5+2=7cm$