Question: So i want 12.6666667 to show up as 12.6 and not 13 or 12.67
This is what i have done

```
Math.Round((5 * (53 - 32)) / 9, 1)

```

Answer: 
```
d -= d % 0.1; //Where 0.1 is the desired least significant unit.

```

It should truncate rather than round at whatever precision you would like, and it seems to work fine on negative numbers as well, always rounding towards zero.
See [Decimal formatting without rounding .net](https://stackoverflow.com/questions/1138217/decimal-formatting-without-rounding-net)
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