Mike can plow a field in 12 hours and his brother phil can plow it in 15 hours. how long will it take them to plow it if they use two plows and work together?

The difference between two numbers is one. three times the larger number minus two times the smaller number is 9. what are the two numbers

The perimeter of △cde is 55 cm. a rhombus dmfn is inscribed in this triangle so that vertices m, f, and n lie on the sides cd , ce , and de respectively. find cd and de if cf=8 cm and ef=12 cm. the answer is not cd=20 and de=15. i have tried that one, it does not work.

Atown has a population of 7000 and grows at 3% every year. to the nearest year, how long will it be until the population will reach 12400?