Final answer:
For a 7-year-old in need of CPR, the recommended compression to ventilation ratio is 30 compressions to 2 ventilations.
Step-by-step explanation:
The correct compression to ventilation ratio for CPR on a 7-year-old female is 30:2. For children (ages 1 to puberty), one should perform 30 compressions followed by two breaths. This pattern is designed to provide high-quality CPR which is essential for maintaining blood flow to the child's brain and other vital organs. The focus is on performing strong and effective chest compressions (at least 5 cm deep and at a rate of 100 compressions per minute) and providing artificial respiration to support oxygenation. It is imperative to continue CPR until the child regains spontaneous contraction or emergency services take over.