Radius of 1 solid iron sphere =r
→ Volume =34πr3
→ Volume of 27 solid iron
spheres =27x34πr3
→ 34πr'3=27x34πr3
r'3=2πr3
→r'=3r
(ii) Surface area =4+πr2
SA r'=4πr'2
=4π(3r)2=36πr2
S'S=36πr24πr2=91=1:9
Step-by-step explanation:
X= 2, y= -6
X= 0, y= 0
X= -2, y= 6
X= -4, y= 12
X= - 7, y= 21
The formula of the area of a circle is :

You know that the area is 1256.
So :

Divide both sides by

:

<span> take the square root of both sides in order to obtain r :
</span>


<span>
In short, the answer would be 20 (i have rounded).
Hope this helps !
Photon
</span>
Let's set up a formula for this, where x is the amount of dvds he started with:
x-45+10=15
x-35=15
+35 +35
x=50
He had 50 DVDs to begin with.
Check
50-45+10
=15
What’s something goes up but never comes down?