It will take her 5 5/8 hours to read 3/4 of the book
<h3>Ratio and proportions</h3>
Given that Elisabeth reads 1/5 of her book in 1 1/2 hours, this is expessed as:
0.2 of a book = 1.5 hours
In order to determine the time taken to read 0.75 part of the book, we will have:
0.75 of a book = x
Take the ratios
0.2/0.75 = 1.5/x
0.2x = 1.125
x = 1.125/0.2
x = 5.625
Hence it will take her 5 5/8 hours to read 3/4 of the book
Learn more on ratio and proportion here: brainly.com/question/19994681
The above series is a Geometric series because:
t2/t1 = t3/t2 --> 14/7 = 28/14 --> 2 = 2
and common ratio (r)=2
The for S12 we have,
S12 = a(1 - r^12) /(1-r) where, a = first term = 7
or, s12 = 7*(1 - 2^12) / (1 - 2)
= 28665
Answers:
- 3. E) -0.8
- 4. True
- 5. True
- 6. True
- 7. D) 17.62%
=========================================
Explanations:
3. We have negative correlation because the regression line is going downhill (move from left to right). The points are fairly close to the same regression line, so I'd say we have either moderate or fairly strong negative correlation. That means r is fairly close to -1. It's not -1 exactly since that would have to mean all points are on the same line.
-----------------
4. Negative correlation goes with negative r values. Refer to problem 3. Positive correlation goes to positive r values. The r value will most likely not equal the slope value, but they share the same sign.
----------------
5. If r is close to +1, then we have fairly strong positive linear correlation. If r is close to -1, then we have fairly strong negative linear correlation. If r = 0 or close to it, then we should use some other kind of regression tool. Or perhaps the data points are simply randomly scattered about and they have no pattern at all.
-----------------
6. Refer to problem 5.
-----------------
7. Plug in x = 15 and you should find that y = -0.632(15)+27.1 = 17.62, which means that the estimated tip is roughly 17.62% of the bill.
It's 4. Y=in(x)-5
Formula: Y= +/- a( x - h) + k
K= up/down
h= Right/left