At what rate should the amount of Php3,000 be invested to earn a simple interest of Php450 annually?
6
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15
12
Can you please explain to me how you got your answer??


Sagot :

Ummmm, miss, this problem of yours is an example of a problem that uses the formula of simple interest:

Principal x Rate x Time = Simple Interest   or simply
PRT = I ( I means simple Interest)

Here, in your problem, these are the given:

Principal = P 3, 000
Rate = ? 
Time = 1 ( it is 1 because of the word "annually" which means every year or every 1 year)
Simple Interest = P 450

We plot them using the same formula"

P x R x T = I

P 3, 000 x R x 1 = P 450

P 3, 000 x R = P 450  ( right now, we just divide P 450 by P 3, 000 to get the answer) 

P 450 / P 3, 000 = R

0. 15 = R ( no more peso sign because it is already cancelled)

0. 15 = R ( the only thing you will do is to change the 0 . 15 to percent because it is a decimal and to change decimals into percent, we multiply them by 100 and then, change the decimal point into the percent symbol ( % )

 0 . 15 x 100 = R

15 % = R

Therefore, the rate is 15 %.

Answer:
                  15 %