Statistics Homework Help

About Statistics

Statistics is how data is summarised, pictured and reasoned about, and in school it usually arrives in two halves: describing a set of figures, and working out how likely something is. The questions here are mostly the second kind — dice, coins, coloured balls drawn from a bag, tree diagrams — mixed with frequency tables, means from grouped data, and the graphs that go with them.

Popular topics in Statistics

• Probability

  Single and combined events, with and without replacement, mutually exclusive and independent events, and tree diagrams.

• Mean, Median & Mode

  Averages from a list, from a frequency table and from grouped data, including the assumed-mean (coding) method.

• Frequency Distributions

  Building a grouped frequency table, class boundaries and midpoints, and cumulative frequency curves.

• Charts & Graphs

  Bar charts, pie charts, histograms with unequal widths, frequency polygons and what each one is appropriate for.

• Spread

  Range, quartiles and the interquartile range, variance and standard deviation, and comparing two data sets.

• Correlation & Regression

  Scatter diagrams, the line of best fit, the correlation coefficient and the difference between correlation and cause.

• Sampling

  Population and sample, random and stratified sampling, bias, and why a sample must be representative.

• Distributions

  The binomial and normal distributions, expected value, and reading probabilities from standardised scores.

How ScanSolve helps with Statistics

Photograph a table or a tree diagram and ScanSolve sets out the calculation in the order examiners expect: the table completed first, then the totals, then the average or probability that the question asks for. For grouped data it shows the midpoints it is using, because that is the step most often skipped and most often wrong.

Probability answers state the sample space before they state a fraction, and say whether the events are independent or exclusive — the two words that decide whether you multiply or add. Where a question can be done by tree diagram or by formula, the solution shows the tree, since it is easier to check.

Study tips for Statistics

1. 01

   Write the sample space out for small problems. "A die is rolled" has six outcomes; listing them once prevents nearly every probability slip.

2. 02

   Multiply for "and", add for mutually exclusive "or". Deciding which word the question used is the whole of the difficulty.

3. 03

   For grouped data, remember you are estimating: the midpoint stands in for every value in the class, so your mean is an estimate and should be described as one.

4. 04

   Check that probabilities total 1 and frequencies total the stated sample size. Both give you a free check on the arithmetic.

Frequently asked Statistics questions

• How to Calculate Probability: Basic, Conditional & Bayes' TheoremLearn how to calculate probability from basic concepts to conditional probability and Bayes' theorem. Clear examples and formulas for statistics and math students.
• Free Mathway Alternative — Unlimited AI Math Solver Without SubscriptionFind the best free Mathway alternative with step-by-step solutions. ScanSolve gives you unlimited math solving with full explanations — no $9.99/mo subscription.
• Standard Deviation Formula: How to Calculate with ExamplesLearn the standard deviation formula for both population and sample data. Step-by-step calculation guide with examples, variance, and when to use each formula.

More in Maths