1)- 3 1/2 * 2/5 = - 7/2 * 2/5 = - 7/5 = - 1 2/5
2)3/8 * 12/5 = 36/40= 9/10
3)1 × 3/10 = 3/10
4)- 1 2/5 - 9/10 = - 7/5 - 9/10 = (-7 × 2 - 9 × 1)/10 = -14/10 - 9/10 = - 23/10 = - 2 3/10
5)- 2 3/10 + 3/10 =- 23/10 + 3/10 = -23 /10 + 3/10 = - 20/10 = - 2