Verified answer

2.7 - 0.8 = 1.9 = 19/10

19/10 * 2 1/3 = 19/10 * 7/3

5.2 - 1.4 = 3.8 = 38/10

38/10 : 3/70 = 38/10 * 70/3

19/10 * 7/3 : (38/10 * 70/3) = 19/10 * 7/3 * 10/38 * 3/70 = 1/20

(1/20 + 1/8) : 2 1/2 = (1/20 + 1/8)*2/5 = 1/20 * 2/5 + 1/8*2/5 = 1/50 + 1/20 = 7/100

7/100 + 0.43 = 7/100 + 43/100 = 50/100 = 0.5 = 1/2