Answer:
(mn+n²)/(m+n)
Step-by-step explanation:
probability of blue marble= n/(n+m)
probability of red marble= m/(n+m)
probability that process stops = Probability of both blue + probability of both red= n/(n+m) × n/(n+m) + m/(n+m)×m/(n+m)
= (n²+m²)/(n+m)²
P(1st marbel is blue)= P(blue and red) + P(blue and blue)
= mn/(n+m) + n²/(n+m)
= (mn+n²)/(m+n)
P(1st marble is blue | process stops)= ( (mn+n²)/(m+n)× (n²+m²)/(n+m)²)/ ((n²+m²)/(n+m)²)
= (mn+n²)/(m+n)
In the balanced reaction
2 Fe + O₂ → 2 FeO
2 moles of iron (Fe) react with 1 mole of molecular oxygen (O₂) to produce 2 moles of iron oxide (FeO). The ratio of Fe to FeO is 1-to-1, so if one starts with 42.4 mol of Fe, one will end up with the same amount of FeO, 42.4 mol.
Look up the molar mass of Fe and O:
• Fe = 55.845 g/mol
• O = 15.999 g/mol
Then the molar mass of FeO is approximately 71.835 g/mol, and so the mass of 42.4 mol of FeO is
(42.4 mol) × (71.835 g/mol) ≈ 3050 g
Answer:
D (x-10)
Step-by-step explanation:
x^2 - 8x - 20
(x -10)(x+2)
Answer:
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Step-by-step explanation:
The equation of a circle is given by:
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Where (h, k) is the center and r is the radius.
The center of the circle is (1, -4).
And the radius is 3.
Substitute:
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Simplify. Thus, our equation is:
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Ben drinks 3 1/2 liters of tea every 40 minutes.
This means that he would drink 1 3/4 of tea every 20 minutes (divide both sides by 2).
Now, let's multiply each side by 3.
1.75 * 3 = 5.25 (aka 5 1/4)
20 * 3 = 60 minutes (an hour)
He drinks 5 1/4 liters of tea in one hour.