## $$x$$ is between

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### $$x$$ is between

by Gmat_mission » Thu Oct 01, 2020 7:06 am

00:00

A

B

C

D

E

## Global Stats $$x$$ is between

A. 4 and 5
B. 5 and 6
C. 6 and 7
D. 7 and 8
E. 8 and 9

Source: Magoosh

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### Re: $$x$$ is between

by psarma » Thu Oct 01, 2020 3:21 pm
Right angled triangle,
so $$x^2$$ + 10 = $$\left(2\sqrt{\left(15\right)}\right)^2$$
Solving for x:
$$x^2$$ =50
or x= $$\sqrt{50}$$
Thus, answer is Option D - between 7 & 8

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### Re: $$x$$ is between

by [email protected] » Tue Oct 06, 2020 3:19 am
Gmat_mission wrote:
Thu Oct 01, 2020 7:06 am
GMAT_PS_Magoosh_200.png

$$x$$ is between

A. 4 and 5
B. 5 and 6
C. 6 and 7
D. 7 and 8
E. 8 and 9

Solution:

Using the Pythagorean theorem, we have:

x^2 + (√10)^2 = (2√15)^2

x^2 + 10 = 60

x^2 = 50

x = √50

Since 49 < 50 < 64, √49 < √50 < √64. That is, 7 < x < 8.