Jonah's favourite number is a positive integer. One day, he decided to write down all of the positive integers starting at 1 and ending with his favourite number. He noticed, in doing so, that he wrote the digit 7 exactly 30 times. What is Jonah's favourite number?

Situation: . find the substance's half-life, in days. round your answer to the nearest tenth. a 11 gram sample of a substance that's used to treat thyroid disorders has a k. value of 0.1247. enter the correct answer n - noekt done no - initial mass (at time t = 0) n - mass at timet k a positive constant that depends on the substance itself and on the units used to measure time t= time, in days