{
  "problem": "A circle with circumference $20\\pi$ has an arc with a $54^\\circ$ central angle. What is the length of the arc? ${20\\pi}$ ${54^\\circ}$ $\\color{#DF0030}{3\\pi}$",
  "hints": [
    "The ratio between the arc's central angle",
    "$\\theta$",
    "and",
    "$360^\\circ$",
    "is equal to the ratio between the arc length",
    "$s$",
    "and the circle's circumference",
    "$c$",
    "$\\dfrac{\\theta}{360^\\circ} = \\dfrac{s}{c}$",
    "$\\dfrac{54^\\circ}{360^\\circ} = \\dfrac{s}{20\\pi}$",
    "$\\dfrac{3}{20} = \\dfrac{s}{20\\pi}$",
    "$\\dfrac{3}{20} \\times 20\\pi = s$",
    "$3\\pi = s$"
  ]
}
{'source': 'AMPS', 'file': 'amps/khan/356/1608186069.json'}