/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 6 Nickels falling over You may fee... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Nickels falling over You may feel it’s obvious that the probability of a head in tossing a coin is about 1/2 because the coin has two faces. Such opinions are not always correct. Stand a nickel on edge on a hard, flat surface. Pound the surface with your hand so that the nickel falls over. Do this 25 times, and record the results. (a) What’s your estimate for the probability that the coin falls heads up? Why? (b) Explain how you could get an even better estimate.

Short Answer

Expert verified
Estimate the probability as 0.4 by calculating \( \frac{10}{25} \) heads up out of 25 trials. Increase trials for better accuracy.

Step by step solution

01

Understanding the Experiment

In the given experiment, we are tasked to determine the probability that a nickel falls heads up when it is placed on its edge on a hard flat surface and then disturbed to fall over 25 times. The results from this experiment will provide us with the data needed to estimate this probability.
02

Performing the Experiment

After conducting this experiment 25 times, you should tally the number of times the nickel falls with the heads side up. Suppose, for instance, out of 25 trials, the coin lands heads up for 10 trials.
03

Calculating the Probability

The probability of an event is calculated as the number of successful outcomes divided by the total number of trials. Using the example from Step 2, where the nickel lands heads up 10 times, the probability \( P \) is given by: \[ P(\text{heads up}) = \frac{\text{Number of heads outcomes}}{\text{Total trials}} = \frac{10}{25} = 0.4 \] Thus, the estimated probability that the nickel falls heads up is 0.4.
04

Understanding the Estimation Process

The probability estimate of 0.4 assumes your results from the 25 trials. Such an estimate indicates that the nickel is unlikely to favor heads as expected if the coin were fair and balanced (i.e., 0.5 or 1/2). However, external factors such as surface friction, nickel imperfections, and throwing technique could influence this estimate.
05

Improving the Estimate

To obtain a more accurate estimate, you could increase the number of trials. Larger sample sizes generally provide better representations of the inherent probability. Consider repeating the experiment for 100 or even 1000 trials and determining the probability based on this larger dataset.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Experimental Probability
Experimental probability is an empirical way of determining an event's likelihood. By conducting an experiment, you can see how often a particular outcome occurs. This is distinct from theoretical probability, which is based on expected outcomes without testing.
Experimental probability gives tangible results that help understand real-world scenarios. For example, by tossing a nickel 25 times and observing how often it lands heads up, we directly measure its tendency. We calculate this probability by dividing the number of successful outcomes (i.e., heads) by the total number of trials.
  • This form of probability accounts for unexpected variables.
  • It reflects real conditions rather than ideal assumptions.
  • Its accuracy increases with more trials, representing more reliable data.
However, results might vary slightly each time due to the randomness and external factors involved. Increasing the number of trials helps reduce this variance and provides a more consistent estimate.
Coin Toss Experiment
The coin toss experiment is a classic way to explore probability. Typically, each side of a coin (heads or tails) has an equal chance of facing up: a theoretical 1/2 probability.
However, in practice, the environment can change these odds. For example, when you stand a nickel on its edge and disrupt its stability, like in the original experiment mentioned, various factors like surface texture and air turbulence could affect results. Conducting this experiment offers a glimpse into potential deviations from traditional theoretical outcomes.
This experience can be surprisingly different from simply flipping a coin.
  • The surface can influence the way a coin lands.
  • Human interaction can further influence the results.
  • It's a fun and educational way to understand probability concepts.
By performing this experiment, you get to test and question the assumptions about likelihood in controlled settings.
Statistics
Statistics is a branch of mathematics dealing with data collection, analysis, interpretation, and presentation. It helps us make sense of the random phenomena that we encounter daily.
The process involves gathering data through repeated experiments, like tossing a nickel, and then analyzing it to infer general principles. In the exercise at hand, statistics help in understanding how consistent the coin falls heads up or tails up, as seen through frequency or likelihood.
  • Descriptive statistics summarize the data collected.
  • Inferential statistics use this summary to make predictions or inferences about a population.
  • Statistics provide the foundation for probability estimation and help in making informed conclusions.
Thus, by applying statistics, one can determine the fairness of the trial results and how they might be applicable in broader contexts.
Probability Calculation
Probability calculation is central to assessing the likelihood of various outcomes. In this context, it involves determining how often heads or tails appear when tossing a coin.
To calculate probability, take the number of successful outcomes (heads or tails) and divide by the total number of trials. Using the example where the nickel lands heads up 10 times out of 25, the calculation would be:
\[ P(\text{heads up}) = \frac{10}{25} = 0.4 \]
This means that in this experimental setup, the nickel showed heads up 40% of the time. The closer this figure is to 0.5, the more balanced the coin is considered. However, if external conditions or a small sample size exist, results could differ.
  • Probability ranges from 0 to 1, where 0 denotes an impossible event, and 1 indicates certainty.
  • A probability of 0.5 suggests equal odds of the two outcomes.
  • Increased trials tend to offer more reliable probability calculations.
Understanding how to calculate probability is crucial for interpreting how often an event could occur based on experimental observations.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Medical risks Morris’s kidneys are failing, and he is awaiting a kidney transplant. His doctor gives him this information for patients in his condition: 90% survive the transplant and 10% die. The transplant succeeds in 60% of those who survive, and the other 40% must return to kidney dialysis. The proportions who survive five years are 70% for those with a new kidney and 50% for those who return to dialysis. (a) Make a tree diagram to represent this setting. (b) Find the probability that Morris will survive for five years. Show your work.

Teens online We saw in an earlier example (page 319) that 93% of teenagers are online and that 55% of online teens have posted a profile on a social-networking site. Of online teens with a profile, 76% have placed comments on a friend’s blog. What percent of all teens are online, have a profile, and comment on a friend’s blog? Show your work.

Probability models? In each of the following situations, state whether or not the given assignment of probabilities to individual outcomes is legitimate, that is, satisfies the rules of probability. If not, give specific reasons for your answer. (a) Roll a die and record the count of spots on the up-face: \(P(1)=0, P(2)=1 / 6, P(3)=1 / 3, P(4)=1 / 3,\) \(P(5)=1 / 6, P(6)=0\) (b) Choose a college student at random and record gender and enrollment status: \(P(\text { female full-time })=\) \(0.56, P(\text { male full -time })=0.44, P(\text { female part-time })=\) \(0.24, P(\text { male part-time })=0.17\) (c) Deal a card from a shuffled deck: \(P(\text { clubs })=\) \(12 / 52, P\) (diamonds \()=12 / 52, P(\text { hearts })=12 / 52\) \(P(\text { spades })=16 / 52\) .

Random assignment Researchers recruited 20 volunteers—8 men and 12 women—to take part in an experiment. They randomly assigned the subjects into two groups of 10 people each. To their surprise, 6 of the 8 men were randomly assigned to the same treatment. Should they be surprised? Design and carry out a simulation to estimate the probability that the random assignment puts 6 or more men in the same group. Follow the four-step process.

The probability of a flush A poker player holds a flush when all 5 cards in the hand belong to the same suit. We will find the probability of a flush when 5 cards are dealt. Remember that a deck contains 52 cards, 13 of each suit, and that when the deck is well shuffled, each card dealt is equally likely to be any of those that remain in the deck. (a) We will concentrate on spades. What is the probability that the first card dealt is a spade? What is the conditional probability that the second card is a spade given that the first is a spade? (b) Continue to count the remaining cards to find the conditional probabilities of a spade on the third, the fourth, and the fifth card given in each case that all previous cards are spades. (c) The probability of being dealt 5 spades is the product of the five probabilities you have found. Why? What is this probability? (d) The probability of being dealt 5 hearts or 5 diamonds or 5 clubs is the same as the probability of being dealt 5 spades. What is the probability of being dealt a flush?

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.