00:01
So in this question for phyllis we have amount invested by phyllis is $57 ,000 and this is given in the question.
00:19
Now on this he earns interest of 5 % on certain amount while on certain amount he earns interest of 7%.
00:28
So let the amount invested at 5%.
00:39
Percent will be x so amount invested at 7 percent will be 57 000 minus x and in the question it is given that in one year the interest earned over one year is equal to 3 ,290 so we have to find the amount that has been invested 5 % per year and the amount that is invested at 7 % per year.
01:24
So we know that interest, that is i equals p into r into t, where i equals interest and p is the principal amount, r is the rate of interest and t is the time.
01:57
So we can write interest earned over x will be equal to x into 0 .05 and the time is one year.
02:19
So this comes up as 0 .05.
02:23
While the interest earned over 57 ,000 minus x will be equal to.
02:35
0 .07 into 57 ,000 minus x into 1 and this is 0 .07 into 57 ,000 minus x.
02:55
So moving ahead, according to the question, we can write that the interest earned, that is 3 .000...