Answer:

Step-by-step explanation:
How do we find the line that's perpendicular to another?
We find the negative reciprocal. So for example if our slope is 2, the negative reciprocal would be
.
Answer:
The correct answer is OB.
Step-by-step explanation:
Let us recall the Associative Property of Addition: given three real numbers
,
and
the following equality holds:
.
Let us remark that the Associative Property of Addition tells us that we can perform the sums in any order. So,
.
In the other options there was used the Commutative Property of Addition.
Answer:
28 non-blue marbles.
Step-by-step explanation:
Initial probability of choosing a blue marble = 4/12
Let the number of non-blue marbles to be added be x.

(cross multiply)

Answer:
B.
Step-by-step explanation:
A/B × D/C = A/B × D/C because when we divide a fractional number we need to turn the second expression upside down .
Answer: 1. 7
2. 100
3. 193.8
4. 0.8
5. 90.6
Step-by-step explanation:
1. Given the data 9,3,10,12,4,5,12,2
For finding the median we arrange it in ascending order
2,3,4,5,9, 10,12,12
Since the no of observations are even
∴ median =
= 
=
=7
i.e. Median =7
2. Given the data
23, 95,100,23,100,100
Since the no 100 is repeated thrice i.e. the maximum no of times
∴ Mode=100
3.
Given the data
108, 305,252,113, 191
Mean=
=
=193.8
4. Money spent in the first week
= $11.52, $6.48, $5.99, $14.00, and $9.50
Total for the first week
=11.52+6.48+5.99+14.00+9.50
=$47.49
Now she spent $4 more in the second week
i.e.$47.49+4
=51.49$
Increase in mean =
=0.8
5.
Given
2 students scored 100 each
9 students scored 95 each
10 students scored 90 each
3 students scored 80 each
1 student scored 70
Total score of students =
=2265
The average score
=
=90.6