Which expression is equal to a + (b + c)?
(a + b) + c
(a + b) ⋅ c
a + bc
b + ac

The correct option is (a+b)+c

Step-by-step explanation:

The correct option is (a+b)+c

According to the Associative property for Addition:

a+(b+c)=(a+b)+c

The associative property states that you can add or multiply regardless of how the numbers are grouped.

.If you are adding or multiplying it does not matter where you put parenthesis.

Thus the correct option is A

For example, .

If we group the terms differently, it doesn't matter.

This is called the associative property of addition. As long as you still have all of the terms, and there are no other operations (subtraction, multiplication, etc.), the final answer will remain the same no matter how the terms are grouped.

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.

answer: the common difference is -0.10