Question

a first generation iphone is 115 mm long and 61 mm wide what is the perimeter of the first generation iphone

Answer 1

p = 2(l x w)

115 = length
61 = width

155 x 2 = 310
61 x 2 = 122

310 + 122 = 432

Answer 2

Perimeter is:
(Length x 2) + (width x 2)

So basically:
(115 mm x 2) + (61 x 2)

Hope that helps and correct me if I'm wrong!