(3 1/2 - 2 2/3+b+4 3/5)*24=270 2/5

(3 1/2 - 2 2/3+b+4 3/5)*24=270 2/5(3 3/6 - 2 4/6+b+4 3/5)*24=270 2/5(2 9/6 - 2 4/6+b+4 3/5)*24=270 2/5(5/6+b+4 3/5)*24=270 2/5(25/30+b+4 18/30)*24=270 2/5(4 43/30 + b)*24= 270 2/5(163/30 + b)*24= 270 2/5(163*24)/30 + 24b = 270 2/5163*4/5 + 24b = 270 2/524b= 270 2/5 - 652/524b= 270 2/5 - 130 2/524b=140b=140:24b=140/24b= 5 20/24b= 5 5/6