Question

practice
circle the letter of the correct scientific notation for each number.

1. 0.0000001873

a 1.873×10^6
b 187.3×10^5
c 187.3×10^(-8)
d 1.873×10^(-6)

1. 0.0008

e 8×10^4
g 8×10^3
h 8×10^(-4)
j 8×10^(-5)

1. 0.0000562

a 5.62×10^(-6)
b 5.62×10^5
c 5.62×10^(-5)
d 5.62×10^6

1. 0.0005

f 5×10^4
g 5×10^5
h 5×10^(-4)
j 5×10^4

Explanation:

Step1: Recall scientific - notation rule

Scientific notation is of the form $a\times10^{n}$, where $1\leqslant|a|\lt10$ and $n$ is an integer. For a number less than 1, $n$ is negative and its absolute - value is the number of places the decimal point must be moved to the right to get a number between 1 and 10.

Step2: Solve for 0.0000001873

Move the decimal point 7 places to the right to get $a = 1.873$. Since we moved the decimal point 7 places to the right, $n=-7$. So, $0.0000001873 = 1.873\times10^{-7}$. The correct answer is D.

Step3: Solve for 0.0000562

Move the decimal point 5 places to the right to get $a = 5.62$. Since we moved the decimal point 5 places to the right, $n=-5$. So, $0.0000562=5.62\times10^{-5}$. The correct answer is C.

Step4: Solve for 0.0008

Move the decimal point 4 places to the right to get $a = 8$. Since we moved the decimal point 4 places to the right, $n=-4$. So, $0.0008 = 8\times10^{-4}$. The correct answer is H.

Step5: Solve for 0.0005

Move the decimal point 4 places to the right to get $a = 5$. Since we moved the decimal point 4 places to the right, $n=-4$. So, $0.0005=5\times10^{-4}$. The correct answer is H.

Answer:

1. D. $1.873\times10^{-7}$
2. H. $8\times10^{-4}$
3. C. $5.62\times10^{-5}$
4. H. $5\times10^{-4}$