1) jack's brother is nine more than 3/4 of jack's age.
jack is 16 years old, how old is his brother?

Jack's brother is 21 years old

Step-by-step explanation:

let Jack=x

Then, Jack's brother= 3/4x+9

If Jack=16,

enter 16 into the expression

3/4(16)+9

= 12+9

=21

solution:

as, mean is defined as sum of all the observations divided by total number of observations.

and , median is mid value of the data whether arranged in ascending order or descending order.

consider, roadsters:

2,3,4,5,6,7,8,9

mean =

also, median= , because number of observations is even, so median is mean of two mid values.

now, coming to bandits

2,3,4,5,6

mean =  

median = 4, as number of observations is odd.

so, roadsters has greater median as well mean than bandits.

→option a is true about the repairs performed on 2 types of cars:

bandits have lower median and mean than roadsters.

the answer would be 150 books

step-by-step explanation:

if you divide 300 by 2 you will get 150