Ihave 2 separate questions i wish to ask. idk if it's possible, may you show how the problem is solved:
1. how many ounces of a 5% solution and how many ounces of a 15% solution must be mixed to get 40oz of a 9% solution ?
2. last year, taz invested a total of $7500 in two accounts earning simple interest. some of it he invested at 9.5% and the rest was invested at 6.5%. how much did he invest in each account if he earned a total of $577.50 in interest last year?

Initially 100 milligrams of a radioactive substance was present. after 6 hours the mass had decreased by 4%. if the rate of decay is proportional to the amount of the substance present at time t, find the amount remaining after 24 hours. (round your answer to one decimal place.)

What is the first step of an indirect proof of a number that is divisible by two

Dexter read 11 science fiction books and 5 history books. lena read 9 science fiction books and 4 history books. compare the students’ ratios of science fiction books to history books. 1. determine the ratios’ form:    science fiction books to history books 2. write the ratios as fractions:    dexter: 115; lena: 94 3. rewrite with a common denominator. 4. compare. 5. answer the question. determine which shows the correct comparison of the ratios for this problem.