390 minutes in hours
Result
The conversion result is: 390 minutes is equivalent to 6.5 hours.[1]
Conversion formula
How to convert 390 minutes to hours?
We know (by definition) that: 1 min ≈ 0.016666667 hr.
We can set up a proportion to solve for the number of hours.
1 min / 390 min ≈ 0.016666667 hr / x hr
Now, we cross multiply to solve for our unknown x:
x hr ≈ (390 min / 1 min) * 0.016666667 hr → x hr ≈ 6.50000013 hr
Conclusion:
390 min ≈ 6.50000013 hr

Conversion in the opposite direction
The inverse of the conversion factor is that 1 hour is equal to 0.153846153846154 times 390 minutes.
It can also be expressed as: 390 minutes is equal to 1 / 0.153846153846154 hours.
Approximation
An approximate numerical result would be: three hundred and ninety minutes is about zero hours, or alternatively, a hour is about zero point one five times three hundred and ninety minutes.
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.