Answer:
A minimum of 10 dimes and 11 quarters is what Alexandra will have
Step-by-step explanation:
Let
d = number of dimes
q = number of quarters
Since she has 21 coins altogether,
d + q = 21------------------------equation 1
- If these coins are worth $3.75 then
0.10 x d + 0.25 x q = 3.75
- which is 0.10d +.25q =3.75
--------------------------equation 2
where $.10 is the value of one dime and $.25 is the value of one quarter
make d the subject of formula from equation 1 d = 21 -q----------equation 3
insert it in equation 2
0.10d +0.25q =3.75
0.10(21-q) + 0.25q = 3.75
0.1(21)-0.1q+0.25q=3.75
2.1 +0.15q = 3.75
0.15q = 3.75-2.1 = 1.65
q = 1.65/0.15 =165/15 =11
- since we have the value of q insert in equation 3
d = 21 - q
d = 21-11
d = 10
Alexandra has 10 dimes and 11 quarters.
from my calculation i can see that the a minimum of 10 dimes and 11 quarters is what Alexandra will have
Answer:
900 sample size
Step-by-step explanation:
To determine the sample size for a proportion, the margin of error formula is used to determine this:


Where p is the proportion, E is the margin of error, n is the sample size, q = 1 - p,
is the z score.
Since the proportion is not known, the sample size needed to guarantee the confidence interval and error is at p = 0.5 and q = 1 - p = 1 - 0.5 = 0.5
E = 5% = 0.05,
= 3. Hence:

Answer:
1/60
Step-by-step explanation:
Answer:
f
(
x
)
=
3
x
3
−
5
x
2
−
47
x
−
15
Explanation:
If the zero is c, the factor is (x-c).
So for zeros of
−
3
,
−
1
3
,
5
, the factors are
(
x
+
3
)
(
x
+
1
3
)
(
x
−
5
)
Let's take a look at the factor
(
x
+
1
3
)
. Using the factor in this form will not result in integer coefficients because
1
3
is not an integer.
Move the
3
in front of the x and leave the
1
in place:
(
3
x
+
1
)
.
When set equal to zero and solved, both
(
x
+
1
3
)
=
0
and
(
3
x
+
1
)
=
0
result in
x
=
−
1
3
.
f
(
x
)
=
(
x
+
3
)
(
3
x
+
1
)
(
x
−
5
)
Multiply the first two factors.
f
(
x
)
=
(
3
x
2
+
10
x
+
3
)
(
x
−
5
)
Multiply/distribute again.
f
(
x
)
=
3
x
3
+
10
x
2
+
3
x
−
15
x
2
−
50
x
−
15
Combine like terms.
f
(
x
)
=
3
x
3
−
5
x
2
−
47
x
−
15
Answer:
150 to 117 is 25%
340 to 255 is 25%
450 to 351 is 22%
Step-by-step explanation: