Difference between revisions of "2000 AMC 8 Problems/Problem 10"

(Created page with "Shea grows 20%, so she was originally 60/1.2=50 inches tall which is a 10 inch increase. Since Ara grew half as much as Shea, Ara grew 5 inches therefore Ara is now 50+5=55 inche...")
 
(LaTeX solution, added problem and see also)
Line 1: Line 1:
Shea grows 20%, so she was originally 60/1.2=50 inches tall which is a 10 inch increase. Since Ara grew half as much as Shea, Ara grew 5 inches therefore Ara is now 50+5=55 inches tall which is choice E.
+
==Problem==
 +
 
 +
Ara and Shea were once the same height. Since then Shea has grown 20% while Ara has grow half as many inches as Shea. Shea is now 60 inches tall. How tall, in inches, is Ara now?
 +
 
 +
<math>\text{(A)}\ 48 \qquad \text{(B)}\ 51 \qquad \text{(C)}\ 52 \qquad \text{(D)}\ 54 \qquad \text{(E)}\ 55</math>
 +
 
 +
==Solution==
 +
 
 +
Shea has grown <math>20\%</math>, so she was originally <math>\frac{60}{1.2}=50</math> inches tall which is a <math>60 - 50 = 10</math> inch increase. Ara also started off at <math>50</math> inches.  Since Ara grew half as much as Shea, Ara grew <math>10 \div 2 = 5</math> inches.  Therefore, Ara is now <math>50+5=55</math> inches tall which is choice <math>\boxed{E}.</math>
 +
 
 +
==See Also==
 +
 
 +
{{AMC8 box|year=2000|num-b=9|num-a=11}}

Revision as of 19:37, 30 July 2011

Problem

Ara and Shea were once the same height. Since then Shea has grown 20% while Ara has grow half as many inches as Shea. Shea is now 60 inches tall. How tall, in inches, is Ara now?

$\text{(A)}\ 48 \qquad \text{(B)}\ 51 \qquad \text{(C)}\ 52 \qquad \text{(D)}\ 54 \qquad \text{(E)}\ 55$

Solution

Shea has grown $20\%$, so she was originally $\frac{60}{1.2}=50$ inches tall which is a $60 - 50 = 10$ inch increase. Ara also started off at $50$ inches. Since Ara grew half as much as Shea, Ara grew $10 \div 2 = 5$ inches. Therefore, Ara is now $50+5=55$ inches tall which is choice $\boxed{E}.$

See Also

2000 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 9
Followed by
Problem 11
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