Santiago cambió 6 millones de pesos colombianos (COP) a yenes japoneses (JPY) para su viaje a Tokio. La tasa de cambio en ese momento era de 26,7COP por 1JPY. Al regresar del viaje, todavía le quedaban 60.000JPY, los cuales cambió a pesos colombianos, esta vez a una tasa de 25 pesos por yen. ¿Cuánto dinero recibió en pesos al volver de su viaje? ¿Le favoreció la nueva tasa de cambio?

The survey of study habits and attitudes (ssha) is a psychological test that measures the motivation, attitude toward school, and study habits of students, scores range from 0 to 200. the mean score for u.s. college students is about 115, and the standard deviation is about 30. a teacher who suspects that older students have better attitudes toward school gives the ssha to 55 students who are at least 30 years of age. the mean score is 113.2. assume the population standard deviation is 30 for older students what is the margin of error for a 95% confidence interval for the population mean score for a. older students? b. compute the 95% confidence interval for the population mean score for older students. c. compute the 99% confidence interval for the population mean score for older students. d. compute the 88% confidence interval for the population mean score for older students.