The file ”311Call Duration” contains data for the time, in seconds, spent by agents at a certain company talking to 50 customers. (i) Group the data in class intervals of width 40, starting from 60. (ii) Construct a percentage histogram and a percentage polygon. (iii) What can you conclude about call center performance if a call duration target of less than 240 seconds is set?

Call Duration

243

290

199

240

125

151

158

66

350

1141

251

385

239

139

181

111

136

250

313

154

78

264

123

314

135

99

420

112

239

208

65

133

213

229

154

377

69

170

261

230

273

288

180

296

235

243

167

227

384

331