A colony of 15,000 ants increased by 50% after being fed. Then after 4 weeks without food, the number of ants dropped by 60%. What percentage decline did the original population undergo?
A. 72.5
B. 75
C. 90
D. 95.5
E. none of these
সঠিক উত্তরঃ
C.
90
Explanation:

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