Difference between revisions of "1989 AJHSME Problems/Problem 8"

(Solution 1=)
(Solution 2=)
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We use the distributive property to get <cmath>3\times 4+2\times 4+2\times 3 = 26 \rightarrow \boxed{\text{E}}</cmath>
 
We use the distributive property to get <cmath>3\times 4+2\times 4+2\times 3 = 26 \rightarrow \boxed{\text{E}}</cmath>
  
==Solution 2===
+
==Solution 2==
 
Since <math>\frac12+\frac13+\frac14 > \frac12+\frac14+\frac14 = 1</math>, we have <cmath>(2\times 3\times 4)\left(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}\right) > 2\times 3\times 4 \times 1 = 24</cmath>  The only answer choice greater than <math>24</math> is <math>\boxed{\text{E}}</math>.
 
Since <math>\frac12+\frac13+\frac14 > \frac12+\frac14+\frac14 = 1</math>, we have <cmath>(2\times 3\times 4)\left(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}\right) > 2\times 3\times 4 \times 1 = 24</cmath>  The only answer choice greater than <math>24</math> is <math>\boxed{\text{E}}</math>.
  

Revision as of 11:11, 28 August 2021

Problem

$(2\times 3\times 4)\left(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}\right) =$

$\text{(A)}\ 1 \qquad \text{(B)}\ 3 \qquad \text{(C)}\ 9 \qquad \text{(D)}\ 24 \qquad \text{(E)}\ 26$

Solution 1

We use the distributive property to get \[3\times 4+2\times 4+2\times 3 = 26 \rightarrow \boxed{\text{E}}\]

Solution 2

Since $\frac12+\frac13+\frac14 > \frac12+\frac14+\frac14 = 1$, we have \[(2\times 3\times 4)\left(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}\right) > 2\times 3\times 4 \times 1 = 24\] The only answer choice greater than $24$ is $\boxed{\text{E}}$.

Solution 3(Bash)

We can just bash it out, getting $24(\frac12+\frac13+\frac14)= 12 + 8 + 6 = 26 \rightarrow \boxed{\text{E}}$

See Also

1989 AJHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 7
Followed by
Problem 9
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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