Divya has 70 rocks. She donates half of the rocks to a science center. Then she collects 3 rocks on

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:

1. Start with 70 rocks
2. 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