Ratios and unit prices
Compare quantities fairly by finding the amount for one unit.
Get comfortable with the test calculator
1:071-page summary: The GED® Math test calculator: habits that save points
- Part 1 is short and has no calculator: fractions, order of operations, square roots.
- Part 2 gives you the TI-30XS MultiView on the screen, plus a calculator reference sheet and a formula sheet.
- Type the whole problem first, then press enter. Use the ( ) keys.
- Keep fractions as fractions with the fraction key, not the ÷ key.
- For a negative number, use the small (−) key, not the minus key.
- Ask: does this answer make sense?
Read the transcript
The GED® Math test comes in two parts.
Part one is short, and you can't use a calculator. It checks basic number skills, like fractions, order of operations, and square roots. Plan on about 10 minutes.
In part two, you get a calculator. It's the TI-30XS MultiView. On the computer test, it opens on the screen. You also get a calculator reference sheet and a formula sheet.
A few habits help.
Type the whole expression before you press enter, and use the parentheses keys. The calculator follows the order of operations, so 3 plus 4 times 2 gives 11, not 14.
For a fraction, use the fraction key, not the divide key, when you want the answer to stay a fraction.
For a negative number, use the small negative key, not the minus key.
And when you get an answer, ask yourself if it makes sense.
The calculator saves time, but it doesn't do the thinking. Practice with it before test day. GED.com has a free calculator tutorial.
Captions are on by default. Narrated with an AI voice (ElevenLabs).
A ratio compares two quantities
A recipe uses 2 cups of rice for 3 cups of water: a 2:3 ratio. To keep it, multiply both quantities by the same number.
For 4 cups of rice, use 6 cups of water. Adding the same amount to each quantity does not generally keep the ratio.
Use a unit price to compare packs
A 6-pack costs $9: 9 ÷ 6 = $1.50 each. An 8-pack costs $10: 10 ÷ 8 = $1.25 each.
The 8-pack has the lower unit price. It is not automatically the best purchase if you cannot afford or use all eight; the math only compares price per item.
Your turn.
Try each question before opening the explanation. These are FinishHigh practice examples, not GED® test questions.
The rice-to-water ratio is 2:3. How much water for 6 cups of rice?
Show the answer and why
9 cups. Multiply both quantities by 3.
Five notebooks cost $7.50. What is the unit price?
Show the answer and why
$1.50 per notebook. Divide 7.50 by 5.
Which is cheaper per bottle: 3 for $6 or 5 for $9?
Show the answer and why
The 5-pack: $1.80 each compared with $2 each.
Trusted sources and further study
Sources guide the topics and factual information. The lesson wording, examples, and questions are original FinishHigh material.
- Math study booklet ↗GED Testing Service · checked 2026-10-07
- Khan Academy skill practice ↗Khan Academy · checked 2026-10-07
- Get Sum Math practice ↗Get Sum Math · checked 2026-10-07
Another small step
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