Scientific Notation Word Problems (A) - Part A and Part B Answers

Sep 23, 2026

Scientific Notation Word Problems (A) practice converting numbers to scientific notation and solving multi-step word problems that involve addition/subtraction, multiplication, and division with rates, ratios, and scaling. Part A asks students to write given distances, sizes, populations, and other measurements in scientific notation. Part B presents real-world contexts (light vs. sound, measurements, debt totals, computation per minute, astronomy, and genetics) requiring work shown and final answers in scientific notation.

LanguageEnglish

CategoryExam

FormatPDF

Pages4

Reading Time10 min

AccessFree to download

Part A: Write the value in scientific notation

Problems 1-4

Part B: Solve each word problem in scientific notation

Problems 5-16

Answer Key

Name: ______________________________________ Scientific Notation Word Problems (A) Remember: Read carefully to identify the operation. Add/Subtract: same type combined or compared. Multiply: rate × time, or scaling up. Divide: find rate, ratio, or how many fit. Always give your final answer in scientific notation. Part A: Write the value in scientific notation. 1.) The distance from Earth to the Moon is about 384, 000 km. 2.) A red blood cell is about 0.00008 cm wide. 3.) The population of the US is about 330, 000, 000 people. 4.) A hydrogen atom has a diameter of about 0.0000001 mm. Part B: Solve each word problem. Show your work and write your answer in scientific notation. 5.) Light travels 3 × 10⁸ m/s. Sound travels 3.4 × 10² m/s How many times faster is light than sound? 6.) A virusis 2 . 5 × 10⁻⁷m long. A bacterium is 5 × 10⁻⁶ m long. How many times longer is the bacterium? 7.) A country’s national debt is 2.8 × 10⁹ dollars. Another country’s debt is 9.4 × 10⁸ dollars. What is the total combined debt? 8.) Country A has a debt of 2.8 × 10⁹ dollars. Country B has 9.4 × 10⁸ dollars. How much more does Country A owe? Mashup Math LLC | Al[l Rights Reserved | Get More K-12 Math Worksheets at www.mashupmath.com](l Rights Reserved | Get More K-12 Math Worksheets at www.mashupmath.com) 9.) A computer performs 2.5 × 10⁶ calculations per second. How many calculations can the computer perform in one minute (60 seconds)? 10.) The mass of Earth is 5.97 × 10²⁴ kg. The Moon’s mass is 7.35 × 10²² kg. About how many times more massive is Earth? 11.) Light travels 9.5 × 10¹⁵ m in one year. Write this distance in standard form. 12.) A factory produces 2.5 × 10⁴ cars per year. At this rate, how many years to produce 5 × 10⁶ cars? 13.) One mole of atoms is about 6 × 10²³ atoms. Write 6 × 10²³ in standard form. 14.) A DNA base pair is 3.4 × 10⁻¹⁰ m wide. A gene has 5 × 10³ base pairs. How long is the gene? 15.) Neptune is 4.5 × 10⁹ km from the Sun. Mercury is 5.8 × 10⁷ km. About how many times farther is Neptune? 16.) A proton has mass 1.67 × 10⁻²⁷ kg. An electron has mass 9.1 × 10⁻³¹ kg. About how many times more massive is a proton? = Mashup Math LLC | Al[l Rights Reserved | Get More K-12 Math Worksheets at www.mashupmath.com](l Rights Reserved | Get More K-12 Math Worksheets at www.mashupmath.com) ANSWER KEY 1. ) The distance from Earth to the Moon is about 384, 000 km. Write in scientific notation. = 3.84 × 10⁵ km 2. ) A red blood cell is about 0.00008 cm wide. Write in scientific notation. = 8 × 10⁻⁵ cm 3. ) The population of the US is about 330, 000, 000 people. Write in scientific notation. = 3.3 × 10⁸ 4. ) A hydrogen atom has a diameter of about 0.0000001 mm. Write in scientific notation. = 1 × 10⁻⁷ mm 5. ) Light travels 3 × 10⁸ m/s. Sound travels 3.4 × 10² m/ s. How many times faster is light than sound? = 3 × 10⁸ ÷ 3.4 × 10² ≈ 8.8 × 10⁵ times faster 6. ) A virus is 2.5 × 10⁻⁷ m long. A bacterium is 5 × 10⁻⁶ m long. How many times longer is the bacterium? = 5 × 10⁻⁶ ÷ 2.5 × 10⁻⁷ = 20 times longer 7. ) A country’s national debt is 2.8 × 10⁹ dollars. Another country’s debt is 9.4 × 10⁸ dollars. What is the total combined debt? = 2.8 × 10⁹ + 0.94 × 10⁹ = 3.74 × 10⁹ dollars 8. ) Country A has a debt of 2.8 × 10⁹ dollars. Country B has 9.4 × 10⁸ dollars. How much more does Country A owe? = 2.8 × 10⁹ − 0.94 × 10⁹ = 1.86 × 10⁹ dollars 9. ) A computer performs 2.5 × 10⁶ calculations per second. How many in one minute (60 seconds)? = 2.5 × 10⁶ × 6 × 10¹ = 1.5 × 10⁸ calculations Mashup Math LLC | Al[l Rights Reserved | Get More K-12 Math Worksheets at www.mashupmath.com](l Rights Reserved | Get More K-12 Math Worksheets at www.mashupmath.com) 10. ) The mass of Earth is 5.97 × 10²⁴ kg. The Moon’s mass is 7.35 × 10²² kg. About how many times more massive is Earth? = 5.97 × 10²⁴ ÷ 7.35 × 10²² ≈ 81 times more massive 11. ) Light travels 9.5 × 10¹⁵

FAQs

What does the worksheet require for final answers?

All final answers must be written in scientific notation, and Part B requires showing work as well.

How does the worksheet distinguish operations like multiply and divide from the wording?

It directs students to look for clues: add/subtract involves the same type being combined/compared; multiply uses rate × time or scaling up; divide is used for rate/ratio or how many fit.

What kinds of contexts appear in Part B?

Part B includes comparing light and sound speeds, comparing lengths of a virus and bacterium, combining or subtracting national debt, converting calculations per second to per minute, and astronomy and biology scaling problems.

Sep 23, 2026

Uploaded by Aria Callaghan