+0

# scientic notation in grams

0
691
1
+97

A sample of microbes weighs 50 mg. There are approximately 2.5 × 106 microbes in the sample. What is the approximate mass of each microbe expressed using scientific notation in grams.

May 7, 2015

### Best Answer

#1
+25274
+5

A sample of microbes weighs 50 mg. There are approximately 2.5 × 106 microbes in the sample. What is the approximate mass of each microbe expressed using scientific notation in grams.

$$\small\text{ \begin{array}{lcl} \mathbf{\dfrac{50~mg}{2.5\cdot 10^6~microbes} \cdot \dfrac{1~g}{1000~mg} } \\\\ \mathbf{ =\dfrac{50}{2.5\cdot 10^6\cdot 1000} \cdot \dfrac{g}{ microbe } } \\\\ \mathbf{ =\dfrac{50}{2.5\cdot 10^6\cdot 10^3} \cdot \dfrac{g}{ microbe } } \\\\ \mathbf{ =\dfrac{50}{2.5\cdot 10^9 } \cdot \dfrac{g}{ microbe } } \\\\ \mathbf{ =\dfrac{50}{2.5 } \cdot 10^{-9} \cdot \dfrac{g}{ microbe } } \\\\ \mathbf{ =20 \cdot 10^{-9} \cdot \dfrac{g}{ microbe } } \\\\ \mathbf{ =20 \cdot \dfrac{ng}{ microbe } } \qquad ng =  Nano gram \end{array}\\ }}$$

the approximate mass of each microbe  is 20 ng (Nano gram) or $$\small{\text{20 \cdot 10^{-9} ~g}}$$

.
May 7, 2015

### 1+0 Answers

#1
+25274
+5
Best Answer

A sample of microbes weighs 50 mg. There are approximately 2.5 × 106 microbes in the sample. What is the approximate mass of each microbe expressed using scientific notation in grams.

$$\small\text{ \begin{array}{lcl} \mathbf{\dfrac{50~mg}{2.5\cdot 10^6~microbes} \cdot \dfrac{1~g}{1000~mg} } \\\\ \mathbf{ =\dfrac{50}{2.5\cdot 10^6\cdot 1000} \cdot \dfrac{g}{ microbe } } \\\\ \mathbf{ =\dfrac{50}{2.5\cdot 10^6\cdot 10^3} \cdot \dfrac{g}{ microbe } } \\\\ \mathbf{ =\dfrac{50}{2.5\cdot 10^9 } \cdot \dfrac{g}{ microbe } } \\\\ \mathbf{ =\dfrac{50}{2.5 } \cdot 10^{-9} \cdot \dfrac{g}{ microbe } } \\\\ \mathbf{ =20 \cdot 10^{-9} \cdot \dfrac{g}{ microbe } } \\\\ \mathbf{ =20 \cdot \dfrac{ng}{ microbe } } \qquad ng =  Nano gram \end{array}\\ }}$$

the approximate mass of each microbe  is 20 ng (Nano gram) or $$\small{\text{20 \cdot 10^{-9} ~g}}$$

heureka May 7, 2015