14.8
148 rounded to the nearest tenths is 148.0
You don't need a number line or anything to round 148 to the nearest tent. It is already rounded to that degree (and more).
It is 232.4 when rounded to the nearest tenth
It is then 56.5 when rounded to the nearest tenth
It is then 52.8 when rounded to the nearest tenth
It is then 20.2 when rounded to the nearest tenth
It is 0.8 when rounded to the nearest tenth
4.4
54.4
2.7
28.6
346.21 rounded to the nearest tenth is 346.2.