james invested some money at 13% interest. James also invested $199 more than 3 times that amount at 12%. How much is invested at each rate if James receives $1561.50 in interest after one year? (Round to two decimal places if necessary.)

9514 1404 393

Step-by-step explanation:

Let x represent the amount invested at 13%. Then (3x+199) is the amount invested at 12%. The total interest earned in 1 year is ...

  (13%)(x) +(12%)(3x+199) = 1561.50

  0.49x +23.88 = 1561.50 . . . . simplify

  0.49x = 1537.62 . . . . . . . . . . subtract 23.88

  x = 3138 . . . . . . . . . . . . . . . . divide by 0.49

  3x+199 = 9613

$3138 was invested at 13%; $9613 was invested at 12%.

36 girls

step-by-step explanation:

the 48 boys is 4 parts of the ratio

divide 48 by 4 to obtain one part of the ratio

= 12 ← 1 part of the ratio

3 parts = 3 × 12 = 36 ← number of girls

900 degrees

step-by-step explanation: