Element X is a radioactive isotope such that every 16 years, its mass decreases by half. Given that the initial mass of a sample of Element X is 5900 grams, how much of the element would remain after 27 years, to the nearest whole number?

Which expression is equivalent to 8(k + m) − 15(2k + 5m)?

How much dextrose 70% must be mixed with dextrose 5% to prepare 1,000 ml of dextrose 20%?

Cody started biking to the park traveling 15 mph, after some time the bike got a flat so cody walked the rest of the way, traveling 4 mph. if the total trip to the park took 6 hours and it was 46 miles away, how long did cody travel at each speed? solve using rate times time= distance