The average human body cell is about 5.1 \cdot 10^{-4} \text{ cm}5.1⋅10 −4 cm5, point, 1, dot, 10, start superscript, minus, 4, end superscript, start text, space, c, m, end text in diameter. The diameter of a plant cell is 8 \cdot 10^{-3} \text { cm}8⋅10 −3 cm8, dot, 10, start superscript, minus, 3, end superscript, start text, space, c, m, end text.

Total diameter of human body cell and plant cell can be given by adding both diameter. Total diameter of human body cell and plant cell  is

Given-

Diameter of the human body cell is

Diameter of the plant cell is,

Total diameter of human body cell and plant cell can be given by adding both diameter. To add or subtract numbers that have exponents you must first make sure that the base and exponent of the two terms you are trying to add or subtract are the same.

Convert the exponents of the plant cell diameter same as the human body cell,

Total diameter of human body cell and plant cell can be calculated as,

Hence, total diameter of human body cell and plant cell  is

For more about the human body cell, follow the link below-

link

cm

Step-by-step explanation:

The question asks "What is the combined diameter (in scientific notation) of the two cells?"

Diameter of human body cell:   cm

Diameter of plant cell:  

The combined diameter is the sum of the two. When adding 2 numbers in scientific notation, we need to have the same exponent to power of 10 in both the numbers. Then we simply keep that power of 10 and add the constants.

Lets make the diameter of human body cell to 10 to the power -3. If we move the decimal point of the constant 1 units left the power decreases 1 units to -3. That's what we want. So:

Now, we add:

cm

on monday rodney ate 1/4th of the sandwich = 3/12

on tuesday he ate 1/3rd of the sandwich = 4/12

therefore in total he has eaten = 3/12 + 4/12 = 7/12

thus we can say that he has eaten 7/12 of the sandwich on monday and tuesday alltogether.

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