$5400 is? invested, part of it at 11? % and part of it at 8? %. for a certain? year, the total yield is ? $522.00. how much was invested at each? rate?

Step-by-step explanation:

Let x represent the amount invested at 11%. Then (5400-x) is the amount invested at 8%. The total interest earned is the sum of the interest amounts earned on each investment. Each of those is the product of the interest rate and the amount invested.

  (5400-x)·8% + x·11% = 522

  432 +0.03x = 522 . . . . . . . . simplify

  .03x = 90 . . . . . . . . . . . . . . . subtract 432

  90/.03 = x = 3000 . . . . . . . . divide by the coefficient of x

$3000 is invested at 11%; $2400 is invested at 8%.

b.an increase in a causes b to decrease

5/12, or 5: 12

step-by-step explanation: