Divya has 70 rocks. She donates half of the rocks to a science center. Then she collects 3 rocks on each of her nature hikes. Write an expression to represent the number of rocks Divya has after she collects rocks on n nature hikes.
For each hike, we have:
Start with 70 rocks
She donates half which is 35, which means she's left with 35
Since each nature hike gives her 3 more rocks, and she goes on n nature hikes, we have the following algebraic expression: 3n + 35
