No.
A chord is a straight segment that joins two points of the circumference. It starts at a point in the circumference and ends at other point in the circumference.
The radius goes from the center of the circle (which is not on the circumference) to one point of the circumference.
The diameter is a chord (the largest chord possible); but not the radius.
Refer to the diagram shown below.
w = 6 7/8 in = 6.875 in, the width of each device.
d = 3 1/2 in = 3.50 in, the space between teo devices.
The total space needed is
D = 4(w+d) + w
= 5w + 4d
= 5*6875 + 4*3.5
D = 48.375 in or 48 3/8 in
Answer: 48 3/8 inches or 48.375 inches
Domain is the x-coordinate and range is the y - coordinate

The answer is 15.
30% of 60 = 18
45% of 60 = 27
27 + 18 = 45
60 - 45 = 15