Difference between revisions of "1985 AJHSME Problems/Problem 5"
(New page: ==Solution== To get the fraction, we need to find the number of people who got grades that are "acceptable" (C and D is "acceptable!?") over the total number of people.<br><br>Finding the ...) |
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+ | ==Problem== | ||
+ | |||
+ | <asy> | ||
+ | unitsize(13); | ||
+ | draw((0,0)--(20,0)); | ||
+ | draw((0,0)--(0,15)); | ||
+ | draw((0,3)--(-1,3)); | ||
+ | draw((0,6)--(-1,6)); | ||
+ | draw((0,9)--(-1,9)); | ||
+ | draw((0,12)--(-1,12)); | ||
+ | draw((0,15)--(-1,15)); | ||
+ | fill((2,0)--(2,15)--(3,15)--(3,0)--cycle,black); | ||
+ | fill((4,0)--(4,12)--(5,12)--(5,0)--cycle,black); | ||
+ | fill((6,0)--(6,9)--(7,9)--(7,0)--cycle,black); | ||
+ | fill((8,0)--(8,9)--(9,9)--(9,0)--cycle,black); | ||
+ | fill((10,0)--(10,15)--(11,15)--(11,0)--cycle,black); | ||
+ | label("A",(2.5,-.5),S); | ||
+ | label("B",(4.5,-.5),S); | ||
+ | label("C",(6.5,-.5),S); | ||
+ | label("D",(8.5,-.5),S); | ||
+ | label("F",(10.5,-.5),S); | ||
+ | label("Grade",(15,-.5),S); | ||
+ | label("$1$",(-1,3),W); | ||
+ | label("$2$",(-1,6),W); | ||
+ | label("$3$",(-1,9),W); | ||
+ | label("$4$",(-1,12),W); | ||
+ | label("$5$",(-1,15),W); | ||
+ | </asy> | ||
+ | |||
+ | The bar graph shows the grades in a mathematics class for the last grading period. If A, B, C, and D are satisfactory grades, what fraction of the grades shown in the graph are satisfactory? | ||
+ | |||
+ | <math>\text{(A)}\ \frac{1}{2} \qquad \text{(B)}\ \frac{2}{3} \qquad \text{(C)}\ \frac{3}{4} \qquad \text{(D)}\ \frac{4}{5} \qquad \text{(E)}\ \frac{9}{10}</math> | ||
+ | |||
==Solution== | ==Solution== | ||
− | To get the fraction, we need to find the number of people who got grades that are " | + | To get the fraction, we need to find the number of people who got grades that are "satisfactory" over the total number of people. |
+ | |||
+ | Finding the number of people who got acceptable grades is pretty easy. 5 people got A's, 4 people got B's, 3 people got C's and 3 people got D's. Adding this up, we just have <math>5+4+3+3 = 15</math>. | ||
+ | |||
+ | So we know the top of the fraction is 15. Only 5 people got "unacceptable" scores, so there are <math>15 + 5 = 20</math> scores. | ||
+ | |||
+ | <math>\frac{15}{20}=\frac{3}{4}</math> is our fraction, so <math>\boxed{\text{C}}</math> is the answer. | ||
+ | |||
+ | ==Video Solution== | ||
+ | https://youtu.be/5KwEd-yul00 | ||
+ | |||
+ | ~savannahsolver | ||
+ | |||
+ | ==See Also== | ||
+ | |||
+ | {{AJHSME box|year=1985|num-b=4|num-a=6}} | ||
+ | |||
+ | [[Category:Introductory Algebra Problems]] | ||
+ | |||
+ | |||
+ | {{MAA Notice}} |
Latest revision as of 09:22, 10 January 2023
Contents
Problem
The bar graph shows the grades in a mathematics class for the last grading period. If A, B, C, and D are satisfactory grades, what fraction of the grades shown in the graph are satisfactory?
Solution
To get the fraction, we need to find the number of people who got grades that are "satisfactory" over the total number of people.
Finding the number of people who got acceptable grades is pretty easy. 5 people got A's, 4 people got B's, 3 people got C's and 3 people got D's. Adding this up, we just have .
So we know the top of the fraction is 15. Only 5 people got "unacceptable" scores, so there are scores.
is our fraction, so
is the answer.
Video Solution
~savannahsolver
See Also
1985 AJHSME (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 |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.