3circles in a rectangle of width 6cm. The first circle of radius 3cm touches the three sides of the rectangle. The second of radius 2cm touch one side of the rectangle and touches the former and the last which is of radius 1.5cm also touching two sides of the rectangle. What is the distance from the center of the first circle of radius 3cm to the center of the third with radius 1.5cm.
I tried working it by construction, and I have AB=7.5cm. But by calculation I am confused