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What is the sum of 1 - 2 + 4 - 8 + 16 - ... + 1024?

 Jan 7, 2021

Best Answer 

 #1
avatar+218 
+2

There are 11 terms and the common ratio is -2. Using the geometric series calculator, the answer is 683.

:D

 Jan 7, 2021
 #1
avatar+218 
+2
Best Answer

There are 11 terms and the common ratio is -2. Using the geometric series calculator, the answer is 683.

:D

AvenJohn Jan 7, 2021
 #2
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0

Using algebra, we can see after subtracting a few numbers, we notice there are 10 numbers, therefore there are 5 pairs and one number.

$ -1, -4, -16, -64, -256, and 1024$

 

$1-2, 4-8, 16-32, 64-128, 256-512, 1024

 

using normal subtraction 

We get 

$683$

 Jan 8, 2021

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