If “statistics” sounds like a college class, take a breath. On the GED it’s much smaller than that.
Adding up a week of tips and working out your average day is statistics. Guessing your chances of grabbing a matching sock in the dark is probability. You’ve done both without a pencil.
The catch? The slips here are tiny, like dividing by 5 when the table has 6 rows. Each one gives a tidy-looking number, and that number is usually waiting among the choices.
On this page you’ll get:
- 25 practice questions (scroll up), new ones every time
- Mean, median, mode and range in plain English
- How to read tables, bar graphs and dot plots fast
- Probability, explained with a sock drawer
Skills in this set: Mean of a data set · Mean of a data set shown in a table · Median of a data set with an even number of values · Mode and range from a dot plot · Finding a missing value from a required mean · Weighted average · Comparing categories on a bar graph · Totals and differences from a two-column table · Reading counts from a dot plot · Reading a circle graph given as percents · Probability of a single event and comparing likelihoods · Probability of the complement of an event · Probability of two independent events · Probability of two dependent events (no replacement) · Counting outcomes with the multiplication principle · Comparing the center and spread of two data sets
What data questions look like, from tips to socks
Almost every data question hands you a table or a graph and asks you to do something small with it: find an average, find the middle, or work out a chance. None of it needs algebra, only careful counting.
The mean is the average. Say your tips for five shifts were $40, $55, $35, $60 and $50. Add them up ($240) and divide by how many there are (5), and your mean is $48 a shift.
The median is the middle value once the list is in order. Sort the tips: $35, $40, $50, $55, $60. The middle one is $50. With an even number of values, take the two in the middle and average them.
The mode is the value that shows up most often, like a tip amount you get again and again (this list has none, since nothing repeats). The range is the gap between your best and worst shift: $60 − $35 = $25.
Those numbers usually come from a table or a graph. You may see bar graphs, circle graphs, dot plots, histograms, box plots, line graphs and scatter plots, and two or three questions can share one graph.
To read one fast, start with the title and the labels. Then check the scale: work out what one gridline is worth before you read any bar. On a dot plot, each dot is one thing, so you just count.
Now the sock drawer. Probability is the chance something happens, written as a fraction: the outcomes you want over all the outcomes. With 4 black socks and 6 white ones, your chance of grabbing black without looking is 4 out of 10, or 4/10.
Pull a second sock without putting the first one back, and the drawer has changed. If the first was black, there are 3 black socks left out of 9, so the chance of another black is 3/9.
For both socks to be black, multiply: 4/10 × 3/9 = 12/90, which is 2/15. Questions nearly always say whether the first item goes back, and that detail decides the math.
Give this part a little extra time. A GED Testing Service session on skill gaps named compound probability (two events in a row) as one of four areas test-takers miss.
The settings are everyday: quiz scores, shift hours, a survey drawn as a circle graph, tiles pulled from a bag. A weighted average usually shows up as a grade where homework, quizzes and the final count for different amounts.
Reading two bars and subtracting needs no calculator, so it could appear in the first five or so questions. A weighted grade is calculator work, and the fraction key will reduce 30/132 to 5/22 for you.
How many questions? Data shares about 20% of the test with geometry, so our estimate is four to six data questions out of about 46. GED Testing Service doesn’t publish counts per topic.
The topics and area weights come from GED Testing Service’s official test guide. It doesn’t publish a question count per topic, so any count here is our estimate.
The 4 mistakes that cost the most points
Each wrong answer in the practice set is the result of one specific slip, and the explanation names it. These are the ones that come up most in this topic.
1Dividing by the wrong count
The mean is the total divided by how many values there are. Add six days of tips and divide by five, and you’ve given yourself a raise you never got. That number looks like an average and sits among the choices, so count the rows and write the number down before you add.
2Finding the median before sorting
The median is the middle of a list in order, and tables on the test are almost never in order. Think of lining people up by height before you point to the one in the middle. Sort from smallest to largest first, and with an even count, average the two middle values.
3Adding chances that should be multiplied
If the question asks for a red bead first and a blue bead second, both things have to happen, so you multiply. Two matching socks in a row is harder than one, so the answer should shrink. Adding makes it grow, which is the giveaway. Circle the word “and” when you see it.
4Forgetting the bag shrinks when nothing goes back
If the first tile stays out, the second draw comes from a smaller bag, like a sock drawer with one sock missing. Take one off the top for that color and one off the bottom for the total, so 6 blue out of 12 becomes 5 out of 11. A choice using 6/12 twice treats the tile as if it went back.
One problem, worked out step by step
A jar holds 4 red, 6 blue and 2 green beads. Two are taken out one after the other without looking, and the first is not put back. What is the probability that both are blue?
The working
- Count the total, then the first draw
Probability is favorable outcomes over total outcomes: 6 of the 12 beads are blue.
4 + 6 + 2 = 12; P(first blue) = 6/12 - Update the jar for the second draw
One blue bead is gone and stays gone, so 5 blue remain out of 11.
P(second blue) = 5/11 - Multiply, since both must be blue
Both events have to happen, so multiply tops together and bottoms together, leaving the fraction unsimplified so you can see where it came from.
6/12 × 5/11 = 30/132 - Simplify and check the size
Divide top and bottom by 6 to simplify. With the bead put back the answer would be 6/12 × 6/12 = 1/4, so the real answer should be a little less.
30/132 = 5/22, or about 0.23
Answer: 5/22, or about 0.23
How to get better at this, fast
- Write the count before the total. For a mean, count the values, write “÷ 6” on your note board, and only then start adding.
- Sort the list first, every time. With the values in order, the middle one is the median, the one that repeats most is the mode, and the last minus the first is the range.
- On every two-draw problem, ask whether the first item went back. If it did, the second fraction matches the first. If it didn’t, take one off the top and one off the bottom, then multiply the two fractions.
- Read the scale before the bars. Work out what one gridline is worth before you read any height, and on a dot plot decide whether “3 or more” includes the column at 3.
Frequently asked questions
Are mean and median on the GED formula sheet?
Yes, both are. Mode (the value that shows up most) and range (largest minus smallest) aren’t, so learn those two.
Is probability on the GED formula sheet?
No, so bring these ideas with you. Probability is the outcomes you want over all the outcomes. The chance of something not happening is 1 minus the chance it happens. When both events must happen, multiply, and if the first item stays out, both parts of the second fraction drop by one.
How many statistics and probability questions are on the GED math test?
GED Testing Service doesn’t publish a count per topic. Data shares about 20% of the test with geometry, so an even split gives about four to six data questions, which is our estimate.
Do I need combinations and permutations for the GED?
They’re listed in the official test guide, but it doesn’t say how often they appear. Our set focuses on the counting principle: multiply the number of choices in each group, like bread, filling and drink for a lunch special.
Keep going
The formula sheet, explained
Mean and median on the sheet, and the probability rules you bring with you.
Fractions, decimals and percents practice
Probabilities are fractions and circle graphs are percents; the conversions matter here.
Geometry and measurement practice
The other half of the measurement category, worth practicing alongside data.