Final answer:
To completely factor the expression by grouping, you can group the terms into pairs and find the greatest common factor of each pair. Then, factor out the greatest common factor from each pair.
Step-by-step explanation:
To completely factor the expression by grouping, we can group the terms into pairs and find the greatest common factor of each pair. Let's group the terms:
(6uy + 10br) + (60ry + bu)
Now, let's factor out the greatest common factor from each pair:
2u(3y + 5r) + b(60r + u)
So, the completely factored expression is 2u(3y + 5r) + b(60r + u).