Patterns and Exponents

powers_of2_0.gifThe numbers 1, 2, 4, 8, 16, 32, 64, 128, 256, ... form a pattern. What is the rule for this pattern?   Answer

This list of numbers results from finding powers of 2 in sequence. Look at the table below and you will see several patterns.

Exponential
Form
Factor
Form
Standard
Form
20 = Any number (except 0) raised to the zero power is always equal to 1. 1
21 = Any number raised to the first power is always equal to itself. 2
22 = 2 x 2 = 4
23 = 2 x 2 x 2 = 8
24 = 2 x 2 x 2 x 2 = 16
25 = 2 x 2 x 2 x 2 x 2 = 32
26 = 2 x 2 x 2 x 2 x 2 x 2 = 64
27 = 2 x 2 x 2 x 2 x 2 x 2 x 2 = 128
28 = 2 x 2 x 2 x 2 x 2 x 2 x 2 x 2 = 256

Can you predict the next two numbers in the list after 256?   Answer 


Example 1: Rewrite the numbers 1, 3, 9, 27, 81, 243, ... as a powers of 3.

Solution:

Exponential
Form
Standard
Form
30 = 1
31 = 3
32 = 9
33 = 27
34 = 81
35 = 243

Can you predict the next two numbers in the list after 243?   Answer 


Example 2: If 73 = 343, then find 74 with only one multiplication.

Solution: 74 = 73 times 7

74 = 343 x 7

74 = 2,401


Example 3: If 45 = 1,024, then find 46 with only one multiplication.

Solution: 46 = 45 times 4

46 = 1,024 x 4

46 = 4,096


Example 4: If 100 = 1,   and 101 = 10,   and 102 = 100,   and 103 = 1,000,   then predict the values of 106 and 108 in standard form.

Solution:

Exponential
Form
Standard
Form
Description
100 = 1 The exponent is 0; the number 1 has no zeros.
101 = 10 The exponent is 1; the number 10 has 1 zero.
102 = 100 The exponent is 2; the number 100 has 2 zeros.
103 = 1,000 The exponent is 3; the number 1,000 has 3 zeros.
106 = 1,000,000 The exponent is 6; the number 1,000,000 has 6 zeros.
108 = 100,000,000 The exponent is 8; the number 100,000,000 has 8 zeros.

Summary: When you find powers of a number in sequence, the resulting list of products forms a pattern. By examining this pattern, we can predict the next product in the list. Given the standard form of a number raised to the nth power, we can find the standard form of that number raised to the n+1 power with a single multiplication. When you find powers of 10 in sequence, a pattern of zeros is formed in the resulting list of products.


Exercises

Directions: Read each question below. Click once in an ANSWER BOX and type in your answer; then click ENTER. Do not include commas in your answers. After you click ENTER, a message will appear in the RESULTS BOX to indicate whether your answer is correct or incorrect. To start over, click CLEAR.


1. The numbers 1, 5, 25, 125, 625, ... are each powers of what number?
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2. In Exercise 1, what is the next number in the list?
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3. The numbers 1, 6, 36, 216, 1296, ... are each powers of what number?
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4. 10,000,000,000,000 is 10 raised to what power?
ANSWER BOX:   

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5. If 14 is equal to 1, then what is 1100?
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