2/3 of the children at a school are scared of snakes, 1/3 are scared of spiders, and 1/6 are scared of snakes and spiders. What fraction of those who are scared of spiders are also scared of snakes?
1/2
1/3
1/6 **my choice but I'm not sure
2/3
(1/6)/(1/3) = (1/6)/(2/6) = 1/2
1/6 of all the kids are scared of both.
Correct Steve!
Assume that the following events are independent:
• probability a high school senior will go to college is 0.69
• probability a high school senior will go to college and live in a dorm is 0.42
What is the probability that a high school senior will live in a dorm, given that the person will go to college? (round to hundredths)
0.61
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1/8 of the boys at a high school tried out for the football team, 1/6
tried out for the baseball team, and 1/12 tried out for the football team and baseball team. What fraction of those who tried out for football also tried out for baseball?
2/3
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Juliet is being tested for a contagious disease. The test is 99% accurate and in actuality, 0.1% of the population has the disease. Juliet still thinks she has the disease even though she tested negative. Is she worrying too much? Explain.
She is worrying too much as the probability that she is sick given she tested negative is 0.0001
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Bob has a standard deck of playing cards. If he randomly draws a J, K, 2, and 2, what is the probability that the next card he draws to add to his hand is a K?
1/16
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Amy has 3 children, and she is expecting another baby soon. Her first three children are girls. What is the probability that the fourth baby is another girl?
0.5 or 50%
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In a school of 1250 students, 250 are freshmen and 150 students take Spanish. The probability that a student takes Spanish given that he/she is a freshman is 30%. What is the probability that a randomly selected student is a freshman given that he/she takes Spanish?
50%
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2/3 of the children at a school are scared of snakes, 1/3 are scared of spiders, and 1/6 are scared of snakes and spiders. What fraction of those who are scared of spiders are also scared of snakes?
1/2
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A women-only gym has 60% of its members married. 75% of the married women exercise in the morning and 30% of the single women exercise in the morning. Are being married and exercising in the morning independent?
No. P(married and exercise in the morning) = 45% & P(married)·P(exercise in the morning) = 34.2%
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Amy has 3 children, and she is expecting another baby soon. Her first three children are girls. Is the sex of the fourth baby dependent or independent of the first three?
Independent. With every child, there is a 50% chance of having a boy or girl.
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Katie has a 75% chance of making an A on a test. What is the probability that she will not make an A on her next two tests: Algebra and Physics?
6.25%
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This took a while to put it on here. Hope people can go here from now on in the future. USA TEST PREP^ for Connexus aswell. Peace.
To find the fraction of those who are scared of spiders and also scared of snakes, we can use the concept of probability.
First, let's find the fraction of children scared of snakes. We are told that 2/3 of the children are scared of snakes.
Next, let's find the fraction of children scared of spiders. We are told that 1/3 of the children are scared of spiders.
Now, we need to find the fraction of those who are scared of snakes and spiders. We are told that 1/6 of the children are scared of both snakes and spiders.
To find the fraction of those who are scared of spiders and also scared of snakes, we divide the fraction of children scared of both snakes and spiders (1/6) by the fraction of children scared of spiders (1/3):
(1/6) ÷ (1/3)
When we divide one fraction by another, we can multiply the first fraction by the reciprocal of the second fraction:
(1/6) x (3/1)
Multiplying the numerators and denominators, we get:
(1 x 3) / (6 x 1) = 3/6
Simplifying the fraction further, we can divide both the numerator and denominator by their greatest common divisor, which is 3:
3/6 = 1/2
Therefore, the fraction of those who are scared of spiders and also scared of snakes is 1/2.