Linear Algebra (Gauss Jordan reduction)

Question

Klein, Jillan and Jielaine assembled 741 newsletters for distribution to students. Klein could assemble 124/h, Jillan 118/hr while Jielaine 132/hr. One morning, the three volunteers worked a total of 6 hrs. If Klein worked for 2 hours, how long did each of Jillan and Jielaine work?

Answer 1

124 t1 + 118t2 +132t3= 741

124*2 + 118*t2 +132*t3 = 741

t2 +t3 = 4 ......Eq1

248 +118t2 +132t3 = 741 ..... or

118t2 +132 t3 = 741 - 248 = 493

118(4 -t3) +132 t3 = 493

472 -118 t3 +132 t3 = 493

14t3 = 493 -472

t3 = 21/14 = 1.5 hr

t2 = 4 -t3 = 4 - 1.5 = 2.5 hr

t1 = 2hr, t2 = 2.5 hr and t3 = 1.5 hr

total = 6hr