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. In what time will * 400 amount to 448 at the rate of 4% per annum. |
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Answer» Answer: COMPLETE step-by-step answer: First, we have Principal AMOUNT = P = Rs. 400 Final Amount = A = Rs. 448 Rate of Interest = R = 4% We will use the formula of Simple Interest that is S.I. = P×R×T/100 , where S.I. = Simple Interest, P = Principal Amount, R = Rate on Interest, T = Time taken in years Now, we will put in the values of P and R in the formula for S.I. So, S.I. = 400×4×T/100 Now SIMPLIFY the value by ELIMINATING 100 from the denominator. We get:- S.I. = 4×4×T=16T We will now use the formula for Final amount which states that:- Final amount = Principal amount + Interest that is A = P + S.I. We will now put the values of P, S.I. and A. So, 448= 400+ 16T This is equivalent to writing:- 16T + 400 = 448 Now, we will take 400 to R.H.S 16T = 448 - 400 = 48 We will now take 16 from 16T to R.H.S So, we get T=4816=3 |
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