(3/4*4/5+8,4)*10=(15/20+16/20+8ц.8/20)*10=8ц.39/20=9ц.19/20*10=9*10+19/20*10=90+19*10/20=90+19*2/2=90+38/2=90+19=99
Если слово "округление" не устраивает, то можно назвать "приближение"
6 целых 200/1000 км или 6 2/10 км или 6 1/5км
3 This is her TV
4 This is them radio
5 This is my lamp
6 This is her bed
7 This is them TV
8 This is his radio
9 This is them lamp
10 This is his bed