How do you change 0.81 into a fraction

Onnie is considering doing some long term investing with money that she inherited. she would like to have $50,000 at the end of 30 years. approximately how much money would lonnie need to put into an account earning 6% interest compounded annually in order to meet her goal?

Jane’s favorite fruit punch consists of pear, pineapple, and plum juices in the ratio 5: 2: 3. chapter reference how much punch can she make if she has only 6 cups of plum juice?

Which number can each term of the equation be multiplied by to eliminate the decimals before solving? 5.6j- 0.12=4+1.1j