Where is Math.round() in Dart?

Yes, there is a way to do this. The num class has a method called round():

var foo = 6.28;
print(foo.round()); // 6

var bar = -6.5;
print(bar.round()); // -7

In Dart, everything is an object. So, when you declare a num, for example, you can round it through the round method from the num class, the following code would print 6

num foo = 5.6;
print(foo.round()); //prints 6

In your case, you could do:

main() {
    print((5.5).round());
}

This equation will help you

int a = 500;
int b = 250;
int c;

c = a ~/ b;

UPDATE March 2021:

The round() method has moved to https://api.dart.dev/stable/2.12.2/dart-core/num/round.html. All the above links are wrong.

Maybe this can help in specific situations, floor() will round towards the negative infinite

https://api.dart.dev/stable/2.13.4/dart-core/num/floor.html

void main() {
 var foo = 3.9;
 var bar = foo.floor();
 print(bar);//prints 3
}