Need explanation of the attached file...........
1. The variable is the daily balance
2. The variable changes thrice i.e., it takes 4 values.
3. The average daily balance for the 30 days is given as 1000
Relevant topic: Weighted average. The clues for identifying this topic are the mention of arithmetic mean and the unequal days (i.e., the weights) for each value.
Solution:(10 *1000 + 5*650 + 5*150 + 10 * x )/ 30 = 1000
The deposit therefore is 1600-150=1450 ( because the balance was already 150 when the deposit was made and so has to be deducted to find the deposit)
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