In which type of inflorescence are older flowers at the base and younger ones at the tip?
In racemose inflorescence, the main axis continues to grow, and older flowers are found at the base while younger ones are at the tip. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Biology Textbook for Class XI and XII (Botany section), Chapter: Morphology and Anatomy of Flowering Plants, Topic: Plant structure and tissue systems.