Mastering Scientific Notation: Sums & Differences Challenge

A scientist measures the mass of a small particle as 3.2 x 10^-27 kg and another particle as 1.5 x 10^-26 kg. What is the total mass of both particles in standard form?

• 4.7 x 10^-27 kg

• 1.0 x 10^-25 kg

• 1.82 x 10^-26 kg

• 2.5 x 10^-26 kg

A comet is traveling at a speed of 2.5 x 10^4 km/h. If it slows down by 1.2 x 10^3 km/h, what is its new speed in standard form?

• 2.4 x 10^4 km/h

• 2.5 x 10^4 km/h

• 2.38 x 10^4 km/h

• 1.2 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 10^15 meters towards the star, how far is it from the star now in standard form?

• 4.05 x 10^16 meters

• 3.9 x 10^16 meters

• 4.5 x 10^16 meters

• 4.0 x 10^16 meters

A bacterium can reproduce every 2 hours, and after 8 hours, there are approximately 2.5 x 10^6 bacteria. If half of them die, how many bacteria remain in standard form?

• 2.0 x 10^6

• 2.5 x 10^5

• 1.0 x 10^6

• 1.25 x 10^6

A cell phone tower emits a signal of 3.0 x 10^-5 watts. If a second tower emits 1.2 x 10^-5 watts, what is the total power emitted by both towers in standard form?

• 3.5 x 10^-5 watts

• 5.0 x 10^-5 watts

• 2.5 x 10^-5 watts

• 4.2 x 10^-5 watts

A researcher finds that a certain chemical is present in a solution at a concentration of 4.5 x 10^-3 mol/L. If another solution has a concentration of 2.0 x 10^-3 mol/L, what is the total concentration when mixed in standard form?

• 4.0 x 10^-3 mol/L

• 5.5 x 10^-3 mol/L

• 7.0 x 10^-3 mol/L

• 6.5 x 10^-3 mol/L

A satellite orbits Earth at a height of 3.6 x 10^7 meters. If it descends by 1.2 x 10^6 meters, what is its new height in standard form?

• 3.6 x 10^7

• 3.6 x 10^6

• 3.588 x 10^7

• 3.5 x 10^7

The volume of a small water droplet is about 2.5 x 10^-9 liters. If you have 4 droplets, what is the total volume in standard form?

• 5.0 x 10^-9 liters

• 1.5 x 10^-8 liters

• 1.0 x 10^-8 liters

• 2.0 x 10^-8 liters

A car travels 1.2 x 10^3 kilometers in a week. If it travels an additional 3.5 x 10^2 kilometers the next week, what is the total distance traveled in standard form?

• 1.55 x 10^3 kilometers

• 1.2 x 10^3 kilometers

• 1.25 x 10^3 kilometers

• 1.9 x 10^3 kilometers

A factory produces 5.0 x 10^4 toys in a month. If production increases by 2.5 x 10^4 toys the next month, what is the new total production in standard form?

• 2.5 x 10^4

• 5.0 x 10^4

• 7.5 x 10^4

• 10.0 x 10^4