A cereal mixture contains rice, wheat and corn in the ratio of 3:7:9. How many kilograms of mixture are there

Janie has $3. she earns $1.20 for each chore she does and can do fractions of chores. she wants to earn enough money to buy a cd for $13.50.

Iknow the answer but the calculator doesn't seem to give the right one

Gia opened two savings accounts at two different banks. one account earns an annual 3.4% simple interest, and the other earns half as much. if she deposited $500 in each account, how much total interest will she have earned in 5 years? a. $34.00 b. $25.50 c. $51.00 d. $510.00