2018 AMC 8 Problems/Problem 5: Difference between revisions
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We can rewrite the given expression as <math>1+(3-2)+(5-4)+\cdots +(2017-2016)+(2019-2018)=1+1+1+\cdots+1</math>. The number of <math>1</math>s is the same as the number of terms in <math>1,3,5,7\dots ,2017,2019</math>. Thus the answer is <math>\boxed{\textbf{(E) }1010}</math> | We can rewrite the given expression as <math>1+(3-2)+(5-4)+\cdots +(2017-2016)+(2019-2018)=1+1+1+\cdots+1</math>. The number of <math>1</math>s is the same as the number of terms in <math>1,3,5,7\dots ,2017,2019</math>. Thus the answer is <math>\boxed{\textbf{(E) }1010}</math> | ||
==See Also== | |||
{{AMC8 box|year=2018|num-b=4|num-a=6}} | {{AMC8 box|year=2018|num-b=4|num-a=6}} | ||
{{MAA Notice}} | |||
Revision as of 15:54, 21 November 2018
Problem 5
What is the value of
?
Solution
Rearranging the terms, we get
, and our answer is
- ProMathdunk123
Solution 2 (slightly different)
We can rewrite the given expression as
. The number of
s is the same as the number of terms in
. Thus the answer is
See Also
| 2018 AMC 8 (Problems • Answer Key • Resources) | ||
| Preceded by Problem 4 |
Followed by Problem 6 | |
| 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
| All AJHSME/AMC 8 Problems and Solutions | ||
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