Difference between revisions of "2019 AMC 12A Problems/Problem 2"
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==Solution 3 (Like Solution 1)== | ==Solution 3 (Like Solution 1)== | ||
− | <math>a = 1.5b</math>. Multiply by 2 to obtain <math>2a = 3b</math>. Since <math>2 = 200\%</math>, the answer is <math>\boxed{200\% | + | <math>a = 1.5b</math>. Multiply by 2 to obtain <math>2a = 3b</math>. Since <math>2 = 200\%</math>, the answer is <math>\boxed{\textbf{(D) }200\%}</math>. |
-DBlack2021 | -DBlack2021 | ||
+ | |||
+ | ==Solution 4 (Like Solution 2)== | ||
+ | WLOG, let <math>b=2</math>. Then, we have <math>a=3</math> and <math>3b=6</math>. Thus, <math>\frac{3b}{a}=\frac{6}{3}=2</math> so <math>3b</math> is <math>200\%</math> of <math>a</math> so the answer is <math>\boxed{\textbf{(D) }200\%}</math>. | ||
==See Also== | ==See Also== |
Revision as of 23:37, 14 February 2019
Contents
Problem
Suppose is
of
. What percent of
is
?
Solution 1
Since , that means
. We multiply by 3 to get a
term, to yield
.
is
of
.
-- eric2020
Solution 2
WLOG, let . Then, we have
and
. Thus,
so
is
or
so the answer is
-21jzhang
Solution 3 (Like Solution 1)
. Multiply by 2 to obtain
. Since
, the answer is
.
-DBlack2021
Solution 4 (Like Solution 2)
WLOG, let . Then, we have
and
. Thus,
so
is
of
so the answer is
.
See Also
2019 AMC 12A (Problems • Answer Key • Resources) | |
Preceded by Problem 1 |
Followed by Problem 3 |
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 |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.