The Earth is approximately 93,000,000 miles from the sun. How would you write this in scientific notation?
A. 9.3 × 106
Incorrect. There are 6 zeros in 93,000,000, but there are seven powers of 10 to place the nine in the 10-millions place.
B. 9.3 × 107
Correct! There are seven powers of 10 in the number.
C. 9.3 × 10-7
Incorrect. This number has seven powers of 10 in it, but they should be positive, not negative.
D. 9.3 × 10-6
Incorrect. There are 6 zeros in 93,000,000, but there are positive seven powers of 10 to place the nine in the 10-millions place.
A nutritional report recommends that people get 0.000015 grams of vitamin D every day. What is this number in scientific notation?
A. 1.5 × 10-5
Correct! This number correctly expresses the negative 5 powers of 10
B. 1.5 × 10-6
Incorrect. The exponent should be -5.
C. 1.5 × 105
Incorrect. The number is less than 1, so the exponent should be -5.
D. 1.5 × 106
Incorrect. The number is less than 1, the exponent should be -5.
The speed of light is 3 × 108 meters per second. What is the number written in standard notation?
A. 3,000,000
Incorrect. You don’t have enough powers of 10.
B. 30,000,000
Incorrect. You don't have enough powers of 10.
C. 300,000,000
Correct! You used the right number powers of 10.
D. 3,000,000,000
Incorrect. You have too many powers of 10.
A typical microwave oven operates at a frequency of 2,450,000,000 Hz. What is this number written in scientific notation?
A. 245 × 109
Incorrect. This number has the correct number of powers of 10, but the coefficient should be 2.45.
B. 245 × 10-9
Incorrect. The exponent should be positive, and the coefficient should be 2.45.
C. 2.45 × 10-9
Incorrect. The exponent should be positive.
D. 2.45 × 109
Correct! This is the correct form of the number.
A full grown blue whale has a weight of approximately 3.6 × 105 pounds. What is this number written in standard form?
A. 36,000,000
Incorrect. You have too many powers of 10.
B. 36,000
Incorrect. You don’t have enough powers of 10.
C. 360,000
Correct! You used the right number powers of 10.
D. 3,600,000
Incorrect. You have too many powers of 10.