Difference between revisions of "1990 AJHSME Problems/Problem 14"
5849206328x (talk | contribs) (Created page with '==Problem== A bag contains only blue balls and green balls. There are <math>6</math> blue balls. If the probability of drawing a blue ball at random from this bag is <math>\fr…') |
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<math>\text{(A)}\ 12 \qquad \text{(B)}\ 18 \qquad \text{(C)}\ 24 \qquad \text{(D)}\ 30 \qquad \text{(E)}\ 36</math> | <math>\text{(A)}\ 12 \qquad \text{(B)}\ 18 \qquad \text{(C)}\ 24 \qquad \text{(D)}\ 30 \qquad \text{(E)}\ 36</math> | ||
| − | ==Solution== | + | ==Solution 1== |
The total number of balls in the bag must be <math>4\times 6=24</math>, so there are <math>24-6=18</math> green balls <math>\rightarrow \boxed{\text{B}}</math> | The total number of balls in the bag must be <math>4\times 6=24</math>, so there are <math>24-6=18</math> green balls <math>\rightarrow \boxed{\text{B}}</math> | ||
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| + | ==Solution 2== | ||
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| + | If b= number of blue balls in the bag and g = number of green balls in the bag then b/(b+g) = 1/4. Substituting b=6 and solving for g we get g=18, or B | ||
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| + | - goldenn | ||
==See Also== | ==See Also== | ||
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{{AJHSME box|year=1990|num-b=13|num-a=15}} | {{AJHSME box|year=1990|num-b=13|num-a=15}} | ||
[[Category:Introductory Probability Problems]] | [[Category:Introductory Probability Problems]] | ||
| + | {{MAA Notice}} | ||
Latest revision as of 19:58, 15 September 2019
Contents
Problem
A bag contains only blue balls and green balls. There are 
blue balls. If the probability of drawing a blue ball at random from this bag is 
, then the number of green balls in the bag is
Solution 1
The total number of balls in the bag must be 
, so there are 
green balls 
Solution 2
If b= number of blue balls in the bag and g = number of green balls in the bag then b/(b+g) = 1/4. Substituting b=6 and solving for g we get g=18, or B
- goldenn
See Also
| 1990 AJHSME (Problems • Answer Key • Resources) | ||
| Preceded by Problem 13 |
Followed by Problem 15 | |
| 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 | ||
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions. 
