Mastering Addition and Subtraction in Scientific Notation

A scientist measures the mass of a small particle as 3.5 x 10^-27 kg. If another particle has a mass of 2.1 x 10^-27 kg, what is the total mass of both particles in scientific notation?

• 4.5 x 10^-27 kg

• 3.0 x 10^-27 kg

• 5.6 x 10^-27 kg

• 6.0 x 10^-27 kg

A comet is traveling at a speed of 4.5 x 10^4 km/h. If it slows down by 1.2 x 10^4 km/h, what is its new speed in scientific notation?

• 4.5 x 10^4 km/h

• 2.3 x 10^4 km/h

• 3.3 x 10^4 km/h

• 5.7 x 10^4 km/h

The distance from Earth to a nearby star is approximately 4.2 x 10^16 meters. If a spaceship travels 1.5 x 10^16 meters towards the star, how far is it from the star now in scientific notation?

• 3.5 x 10^16 meters

• 4.0 x 10^16 meters

• 1.2 x 10^16 meters

• 2.7 x 10^16 meters

A bacterium can reproduce every 20 minutes, and after 3 hours, there are approximately 1.2 x 10^6 bacteria. If 3.0 x 10^5 bacteria die, how many bacteria are left in scientific notation?

• 8.0 x 10^5

• 9.0 x 10^5

• 1.0 x 10^6

• 7.5 x 10^5

A cell phone tower can transmit signals over a distance of 2.5 x 10^3 meters. If a new tower is built that can transmit signals over 1.0 x 10^3 meters less, what is the new transmission distance in scientific notation?

• 1.5 x 10^3 meters

• 3.0 x 10^3 meters

• 2.0 x 10^3 meters

• 1.0 x 10^3 meters

A small planet has a diameter of 1.2 x 10^7 meters. If another planet has a diameter of 3.4 x 10^6 meters, what is the combined diameter of both planets in scientific notation?

• 1.54 x 10^7 meters

• 2.5 x 10^7 meters

• 1.2 x 10^6 meters

• 3.0 x 10^7 meters

A factory produces 5.0 x 10^4 widgets in a day. If production decreases by 1.5 x 10^4 widgets, how many widgets are produced in a day now in scientific notation?

• 4.0 x 10^4

• 2.5 x 10^4

• 5.5 x 10^4

• 3.5 x 10^4

The volume of a small bottle is 2.5 x 10^-3 liters. If you have 1.0 x 10^-3 liters of liquid left in the bottle, how much liquid was originally in the bottle in scientific notation?

• 2.0 x 10^-3 liters

• 3.0 x 10^-3 liters

• 1.0 x 10^-3 liters

• 1.5 x 10^-3 liters

A computer processes data at a rate of 3.0 x 10^9 bits per second. If it processes 1.2 x 10^9 bits less in a certain second, what is the new processing rate in scientific notation?

• 1.8 x 10^9 bits per second

• 1.0 x 10^9 bits per second

• 2.5 x 10^9 bits per second

• 3.5 x 10^9 bits per second

A researcher finds that a certain species of fish can live up to 2.5 x 10^2 days. If a specific fish has lived for 1.0 x 10^2 days, how many days does it have left to live in scientific notation?

• 3.0 x 10^2

• 1.0 x 10^3

• 2.0 x 10^2

• 1.5 x 10^2