23% of what number is 80? can you explain how you get the answer

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.)

Deepak plotted these points on the number line. point a: –0.3 point b: – 3 4 point c: – 11 4 point d: –0.7 which point did he plot incorrectly?

On the day a coffee shop first opened, it had 140 customers. 65% of the customers ordered a large coffee. how many customers ordered a large coffee? enter your answer in the box.