90 deciliters in liters
Result
The conversion result is: 90 deciliters is equivalent to 9 liters.[1]
Conversion formula
How to convert 90 deciliters to liters?
We know (by definition) that: 1 dl ≈ 0.1 liter.
We can set up a proportion to solve for the number of liters.
1 dl / 90 dl ≈ 0.1 liter / x liter
Now, we cross multiply to solve for our unknown x:
x liter ≈ (90 dl / 1 dl) * 0.1 liter → x liter ≈ 9.0 liter
Conclusion:
90 dl ≈ 9.0 liter

Conversion in the opposite direction
The inverse of the conversion factor is that 1 liter is equal to 0.111111111111111 times 90 deciliters.
It can also be expressed as: 90 deciliters is equal to 1 / 0.111111111111111 liters.
Approximation
An approximate numerical result would be: ninety deciliters is about zero liters, or alternatively, a liter is about zero point one one times ninety deciliters.
Footnotes
[1] The precision is 15 significant digits (fourteen digits to the right of the decimal point).
Results may contain small errors due to the use of floating point arithmetic.