Ришить 6 1/3 - 1 2/5=? 7пятнадцатых умножить на 40 =?

1) 61/3 - 12/5 = 305/15 - 36/15 = 269/15 = 17, 14/15 2) 7/15 × 40 = 280/15 = 18, 2/3

6 1/3-1 2/5= 19/3-7/5= 19*5-7*3/15=95-21/15=74/15=4 14/15
7/15*40=7/15*40/1=7*40/15=280/15=56*5/3*5 (сокращаем пятерки)=56/3=18 2/3