Answer:
520 feet.
Step-by-step explanation:
She descended 520 feet because if she started from 540 and ended at 20, we can do 540-20=520 feet.
Step-by-step explanation:
Let
x
be the kg of coffee of brand A in the mix and
y
be the kg of coffee of brand B in the mix.
The total kg must be
50
.
x
+
y
=
50
The cost per kg of the mix must br
$
7.20
. For this, the total cost of the mix will be
6
x
+
8
y
, so the total cost per kg of the mix will be
6
x
+
8
y
50
.
6
x
+
8
y
50
=
7.20
Now that we have our two equations, we can solve.
6
x
+
8
y
=
7.20
⋅
50
6
x
+
8
y
=
360
From the first equation, we can multiply both sides by
6
to get:
6
x
+
6
y
=
300
Subtracting, we get:
2
y
=
60
y
=
30
Thus, we need
30
kg of brand B in our mix. This means that
50
−
30
=
20
kg will be of brand A.
The answers are as follows.
a. 9x
In order to get this, you need to reevaluate 64 as a base of 4. Since 64 is equal to 4^3, we can rewrite the right side as
64^3x = (4^3)^3x = 4^9x
Which gives you the first answer.
b. 10
Similar to the first problem, we need to express 16 as a base of 2. 2^4 is equal to 16, so we use that in it's place and simplify.
16^5/2 = (2^4)^5/2 = 2^20/2 = 2^10
c. Sqrt(7.31)
This one is more simple. Raising something to a 1/2 power (.5) is the same as taking the square root.
100 minus 72 equals to 28. 28% of NOT getting an exam next week
