Powers of Ten
Part of the Numbers & Operations section of Coddy's Pre-Algebra journey. Lesson 36 of 60.
Powers of 10 are the easiest powers there are. 10^2 is 10 × 10, which is 100. 10^3 is 10 × 10 × 10, which is 1000. Each extra factor of 10 adds one more zero.
That is because multiplying by 10 puts a zero on the end of a number. So 10 to a power is a 1 followed by that many zeros: 10^5 is 100000, and 10^6 is 1000000, a million. No multiplying needed, just counting.
A number times a power of 10 works the same way. 3 × 10^5 is 3 × 100000, and multiplying 3 by 100000 puts five zeros after the 3: 300000. Scientists write huge numbers like this, because the exponent tells you the size at a glance.
Challenge
Work out 7 × 10^4. Write the power of 10 out first, then multiply.
Try it yourself
Simplify the expression
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Numbers & Operations
1Working on the Board
Your First AnswerType the Next LineOne Line at a TimeDots and BarsFriendly ProductsRecap: Board Work4Adding Integers
Adding Two NegativesDifferent SignsZero PairsAdding Several IntegersRecap: Adding Integers7Exponents
Repeated MultiplicationSquares and CubesPowers of TenNegative BasesWhere the Minus SitsRecap: Exponents2Order of Operations
Multiply Before AddingLeft to RightParentheses FirstBrackets Inside BracketsThe Fraction Bar GroupsRecap: Order of Operations5Subtracting Integers
Add the OppositeSubtracting a NegativePlus and Minus in a RowDistance Between NumbersRecap: Subtracting Integers