Answer:
C. Marie should make sure she surveys both the fathers and mothers.
a = amount (in oz) of solution A
b = amount of solution B
The scientist wants a mixture of 110 oz, so
a + b = 110
Solution A consists of 65% salt, so each ounce of solution A contributes 0.65 oz of salt; similarly, each ounce of B contributes 0.9 oz. The mixture is supposed to consist of 75% salt, which amounts to 0.75 * (110 oz) = 82.5 oz of salt. So
0.65 a + 0.9 b = 82.5
Solve for a and b:
b = 110 - a
0.65 a + 0.9 (110 - a) = 82.5
0.65 a + 99 - 0.9 a = 82.5
0.25 a = 16.5
a = 66 ==> b = 44
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What are the coefficients in the polynomial 4x²+3x-3?
<u>Coefficient:-</u> A number before a variable
<u>Coefficients in this polynomial:-</u>
4 (the number before x²) and 3 (the number before x)
<h3 />
So we conclude that the right option is:-
4, 3 (Option B)
<h3>Good luck.</h3>
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1 + 1x
OR
1 + x
They mean the same thing! Hope this helps!
<span>Data:
infinite geometric series
A1
= 880
r = 1 / 4
The sum of a geometric series in sigma
notation is:
n 1 - r^n
∑ Ai = A ----------- ; where A = A1
i = 1 1-r
When | r | < 1 the infinite sum exists and is equal to</span><span><span>:
∞ A
∑ Ai = ---------- ; where A = A1
i = 1 1 - r</span>
So, in this case</span><span><span>:
∞ 880
∑ Ai = -------------- = 4 * 880 / 3 = 3520 /3 = 1173 + 1/3
i = 1 1 - (1/4)</span> </span>
Answer: 1173 and 1/3
