Correct option is D
Given:
350 students have food for 40 days.
50 more students join.
Total students = 400.
Find the number of days the food will last.
Concept Used:
Students × Days = Constant (Work–Time inverse relation).
Formula Used:
Students₁ × Days₁ = Students₂ × Days₂
Solution:
350 × 40 = 400 × D
14000 = 400D
D = 14000 / 400
D = 35
Final Answer = 35 days