En grado sexto se desea realizar grupos de trabajo para la actividad del día del idioma. Algunas de las opciones de grupos que se pueden conformar se muestran en la siguiente tabla. Si las variables relacionadas son inversamente proporcionales, ¿cuál es la constante de proporcionalidad?

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10

Find the solution of this system of equation -7x+y=-20 9x-3y=36

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.