Question
A sum of money grows to Rs. 7,500 in 5 years and Rs. 8,250
in 7 years under simple interest. What is the original principal amount?Solution
ATQ,
Difference in interest over 2 years: 8,250 − 7,500 = 750
Annual interest: 750 / 2 = 375
Principal = 7,500 − (5 × 375) = 5,625
The average of the first 7 non-zero multiples of 18 is:
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