Respuesta :

semsee45

Answer:

38.6 units (nearest tenth)

Step-by-step explanation:

Formulae

  • Diameter = 2r
  • Circumference = 2πr

(where r is the radius)

Circumference of a semicircle = diameter + half the circumference

⇒ Circumference of a semicircle = 2r + πr

Given:

  • [tex]\sf radius\:{(r)=7\frac12=7.5[/tex]

[tex]\begin{aligned}\implies \textsf{Circumference of semicircle} & = 2(7.5) + \pi(7.5)\\ & = 15+7.5 \pi\\ & = 38.5619449...\\ & = 38.6\:\sf units\:(nearest\:tenth)\end{aligned}[/tex]
  • Radius=r=7.5units

Circumference

  • πr+2r
  • r(π+2)
  • 7.5(3.14+2)
  • 7.5(5.14)
  • 38.6units²