Multiplication
Multiply (2×103) and (4×102) and express the answer in scientific notation.
8×105
Divide (6.4×106) by (8×102) and express the answer in scientific notation.
8×103
Add (3.5×104) and (2.1×105) and express the answer in scientific notation.
2.45×105
Subtract (9×103) from (5×104) and express the answer in scientific notation.
4.1×104
If a bacterium can divide and double its number every 30 minutes, how many bacteria will there be after 3 hours starting with a single bacterium? Express your answer in scientific notation.
6.4×101 bacteria
(since it doubles 6 times in 3 hours: 26=64, or 6.4×101, and the initial bacterium is 1×100, so 6.4×101×1×100=6.4×101)
Multiply (1.08×10−3)) and (9.3×10−3) and express the answer in scientific notation.
1.0044×10−5
Divide (7.1×106)by (8.2×101) and express the answer in scientific notation.
8.6585×104
Add (8.9×106) and (8.4×106) and express the answer in scientific notation.
1.73×107
Subtract (9×10−5) from (9.24×10−6) and express the answer in scientific notation.
−8.076×10−5
A light-year is approximately 9.461×1012 kilometers. How far will light travel in 3 years? Express your answer in scientific notation.
2.8383×1013 kilometers
(since 3×9.461×1012=2.8383×1013)
Multiply (2×10−4) and (8.1×10−1) and express the answer in scientific notation.
1.62×10−4
Divide (5.4×10−1) by (3.4×101) and express the answer in scientific notation.
1.5882×10−2
Add (8.9×105) and 4, and express the answer in scientific notation.
8.9004×105
Subtract (8.9×106) from (8.4×106) and express the answer in scientific notation.
5×105
The mass of Earth is about 5.972×1024 kilograms, and the mass of the Moon is about 7.347×1022 kilograms. What is the total mass of the Earth and the Moon combined? Express your answer in scientific notation.
6.0454×1024 kilograms
Multiply (2.32×10−6) and (4×10−5) and express the answer in scientific notation.
9.28×10−11
Divide (4×104) by (3.63×10−4) and express the answer in scientific notation.
1.10193×108
Add (6×10−5) and 3, and express the answer in scientific notation.
3.00006×100
Subtract (4×10−5) from (−6) and express the answer in scientific notation.
−6.00004×100
A certain star is 1.5×104 light-years away from Earth. If another star is 10 times farther than this star, how far is the second star from Earth? Express your answer in scientific notation.
1.5×105 light-years
Multiply (3.48×103) and (9.8×104) and express the answer in scientific notation.
3.4104×108
Divide (8.42×103) by (5×102) and express the answer in scientific notation.
1.684×101
Add (6.3×102) and (−6), and express the answer in scientific notation.
5.94×102
Subtract (6×10−5) from 3, and express the answer in scientific notation.
2.99994×100
The diameter of a typical human hair is about 1×10−4 meters. If a bundle contains 1,000 hairs, what would be the combined diameter of these hairs? Express your answer in scientific notation.
Answer 25: 1×10−1
(since 1000=1×103 and
1×10−4 × 1×103 = 1×10−1)