My 11 year old son wants me to show him how to work out a math problem & i can't remember how. 23÷-5=?

Kevin and randy muise have a jar containing 78 coins, all of which are either quarters or nickels. the total value of the coins in the jar is $13.90. how many of each type of coin do they have?

Which of the following represents a number squared is equal to twenty more than nine times that number ? a) x squared = 9x + 20 b) x squared = 20x + 9 c) x squared > 9 + 20x d) x squared = 9 + x + 20

Select the margin of error that corresponds to the sample mean that corresponds to each population: a population mean of 25, a standard deviation of 2.5, and margin of error of 5%