How to write three and nine tenths as a decimal

Ana earns 2.5% simple interest on $2,000 in her savings account. she does not make any deposits or withdrawals. after 3 years, how much interest will ana have earned on her savings account?

Sherrie is baking a pie for her family. she leaves the room and comes back to 35% of the pie having been eaten before she can put the topping on. how much 1 square inch strips of dough will she need for the top, now that a portion is missing? round your answer to the nearest while nimber.

Atown recently dismissed 5 employees in order to meet their new budget reductions. the town had 5 employees over 50 years of age and 19 under 50. if the dismissed employees were selected at random, what is the probability that exactly 2 employees were over 50? express your answer as a fraction or a decimal number rounded to four decimal places.