Which rational number corresponds A on the number line

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

Weekly wages at a certain factory are normally distributed with a mean of $400 and a standard deviation of $50. find the probability that a worker selected at random makes between $450 and $500

Which problem would you use the following proportion to solve for? 24/x = 40/100 a. what is 40% of 24? b. what percent is 24 of 40? c. twenty-four is 40% of what number? d. forty percent of 24 is what number?