Sylvia simplified the expressions on the Expression Comparison Mat shown at right. Some of her work is shown. Are all of her moves “legal”? Explain

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?

Finally, the arena decides to offer advertising space on the jerseys of the arena's own amateur volley ball team. the arena wants the probability of being shortlisted to be 0.14 what is this as a percentage? what is this as a fraction? what is the probability of not being shortlisted? give your answer as a decimal.