Work with radicals and integer exponents.
NC.8.EE.3 Use numbers expressed in scientific notation to estimate very large or very small quantities and to express how many times as much one is than the
other.
Clarification
Checking for Understanding
Students use their knowledge of the base ten number system and
Write the following into scientific notation:
exponents to rewrite numbers using scientific notation. Students
a) The distance between the sun
b) The distance between the sun
interpret scientific notation generated when using technology.
and the Earth is 93,000,000
and Neptune is 2,795,000,000
Students compare numbers written in scientific notation and express
miles.
miles.
the multiplicative relationship between the numbers.
c) A type of fairyfly is the smallest
d) An average bacterium is about
For example: Which of the following represents a larger
known flying insect and is only
0.00004 inches long.
number?
0.0059 inches long.
a) 1.5 x 109
b) 7.5 x 10
Solution: 1.5x10* is the larger number
For your answer, how many times larger is your answer then the
Use the information from above to answer the following questions:
smaller number?
e) In astronomy, the distance between the sun and the Earth is known as 1 AU, or
Solution: 1.5 x 10"is 20 times larger than 7.5 x 10'
astronomical unit. Measured in AUs, what is the distance between the sun and
Notice that 1.5 is .2 times 7.5. Looking at just the 105, 109is 100 times
larger then 10.
Neptune?
(0.2)(100) = 20
f)
If average sized bacteria were placed in a straight line, how many of bacteria
Students should see more than just a division problem but should see
would be needed to equal the length of the smallest known flying insect, a
the multiplicative relationships that are unique to scientific notation.
fairyfly?