Answer:
9
Step-by-step explanation:
8/12=2/3
6/9=2/3
The number of stamps with penny in terms of x is 
<em><u>Solution:</u></em>
Given that,
Ryan has x stamps in his collection
Number of stamps of Ryan = x stamps
Let the stamps with penny be "a"
Ryan has 6 times as many stamps as penny
Therefore,
Number of stamps in Ryan = 6 times as many stamps as penny

Thus number of stamps with penny in terms of x is 
Answer:
1: equivalent
2: equivalent
3: not equivalent
Step-by-step explanation:
for 1 & 2, you just switch the terms, but for 3, the 6z is not negative in the first expression, but it is in the second.
Answer:
Step-by-step explanation:
Given is a table showing the weights, in hundreds of pounds, for six selected cars. Also shown is the corresponding fuel efficiency, in miles per gallon (mpg), for the car in city driving.
Weight Fuel eff. x^2 xy y^2
X Y
28 20 784 560 400
3 22 9 66 484
35 19 1225 665 361
32 22 1024 704 484
30 23 900 690 529
29 21 841 609 441
Mean 26.16666667 21.16666667 797.1666667 549 449.8333333
Variance 112.4722222 1.805555556
Covariance -553.8611111
r -0.341120235
Correlaton coefficient =cov (xy)/S_x S_y
Covariance (x,y) = E(xy)-E(x)E(y)
The correlation coefficient between the weight of a car and the fuel efficiency is -0.341
Each time the previous number is multiplied by 2