Difference between revisions of "2007 AMC 12B Problems/Problem 5"

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==Solution==
 
==Solution==
She must get at least 100-4.5=95.5 points, and that can only be possible by answering at least <math>16 \Rightarrow \mathrm {(D)}</math> questions correct.
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She must get at least 100-4.5=95.5 points, and that can only be possible by answering at least <math>16 \Rightarrow \mathrm {(D)}</math> questions correctly.
 
 
  
 
==See Also==
 
==See Also==
  
 
{{AMC12 box|year=2007|ab=B|num-b=4|num-a=6}}
 
{{AMC12 box|year=2007|ab=B|num-b=4|num-a=6}}

Revision as of 12:47, 17 October 2007

Problem

The 2007 AMC 12 contests will be scored by awarding 6 points for each correct response, 0 points for each incorrect response, and 1.5 points for each problem left unanswered. After looking over the 25 problems, Sarah has decided to attempt the first 22 and leave the last 3 unanswered. How many of the first 22 problems must she solve correctly in order to score at least 100 points?

$\mathrm {(A)} 13$ $\mathrm {(B)} 14$ $\mathrm {(C)} 15$ $\mathrm {(D)} 16$ $\mathrm {(E)} 17$

Solution

She must get at least 100-4.5=95.5 points, and that can only be possible by answering at least $16 \Rightarrow \mathrm {(D)}$ questions correctly.

See Also

2007 AMC 12B (ProblemsAnswer KeyResources)
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 AMC 12 Problems and Solutions