Use the surface area formula of a rectangular prism to find the width. (I have changed it to use the same terms given in the problem).
A
=
2
(
d
w
+
h
w
+
h
d
)
Because of the given information, it is known that:
A
=
208
h
=
8
d
=
6
The width is not know, so let it keep it's variable
w
. But substitute the other values into the equation:
A
=
2
(
d
w
+
h
w
+
h
d
)
208
=
2
[
6
w
+
8
w
+
(
8
)
(
6
)
]
208
=
2
(
14
w
+
48
)
Use the distributive property to solve the right side of the equal sign:
208
=
2
(
14
w
+
48
)
208
=
28
w
+
96
112
=
28
w
112
28
=
w
4
=
w
The width is
4
.
It is volume. The density would be far greater for the books and the atoms as well probably. But volume is just the length x width x height or something.
The answer is choice A, a 3.5% increase.
12/15 = 80%
13/17 = 76.47%
80% - 76.47% = 3.5%
Answers:
A. -12 (6x-5)
C. 6(-12x+10)
Check out the answer A
-12(6x-5)=-12(6x)-12(-5)=-72x+60
Check out the answer C
6(-12x+10)=6(-12x)+6(10)=-72x+60
