Hi,
It is a simple interest question, so there is no big calculations here.
We can eliminate the answer choices D and E.
Because given,
Total investment = 18000
And total interest earned = 2100.
For a moment, let’s assume the amount is equally distributed.
Then,
4% of 9000 + 7% of 9000 = 360 + 630 = 990 for one year.
Total amount for two years is 1980.
Which is less than the actual total interest(2100) given in the question.
So the amount distributed in 4% should be lesser than the amount invested in 7%.
Hence we can eliminate D and E.
Answer as to be either A, B and C.
Also the amount 1980 was not too far from 2100, then the best answer choice to try would be answer choice C.
So,
4% of 7000 + 7% of 11000 = 280 + 770 = 1050 for one year.
Total amount for two years is 2100.
Which matches the amount given in the question.
So the answer is C.
Hope it helps.
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