1. Amy wrote down a 4-digit number. Then Roxanne wrote down the sum of the digits of Amy's number. Mary wrote down the sum of the digits of Roxanne's number. What is the greates possible number Mary could have written down? Justify your answer.

11

Step-by-step explanation:

We may think that in order to have the biggest sum of digits for Mary, we need the biggest number for Amy, so when we sum the digits, we have the biggest number, but that is incorrect:

The maximum number we can have with 4 digits is 9999.

So, The number that Roxanne would write is 9 + 9 + 9 + 9 = 36, and then Mary would write 3 + 6 = 9

But, if the number written by Roxanne was 29, the number of Mary would be 2 + 9 = 11, which is bigger than 9.

So, if the maximum number Roxanne can have is 36, the biggest sum of digits for the numbers from 1 to 36 is achieved with the number 29, that gives us 2 + 9 = 11.

So the greatest number possible Mary could have written down is 11.

we'll this would mean that the dunk tank and the bounce house are the same for 20 hours because the 2 represents that the two activities, and the 20 represents the amount of hours they both are. so with this said, it means that the answer is c. the costs for a dunk tank and bounce house are the same for 20 hours.

c.the costs for a dunk tank and bounce house are the same for 20 hours.

hope this .

the rocket cannot penetrate the ground, in a contextual sense, therefore the roots of this equation should be the domain of this function. i'll let you find the roots of this quadratic equation (hint: use the quadratic formula:  

1- c

2-a

step-by-step explanation:

mark brainliest!