The answer is 11.25 mm.
A diameter of a circle is twice of its radius: d = 2r ⇒ r = d/2
small circle large circle
radius: r1 radius: r2 = ?
diameter: d1 = 15 mm
⇒ r1 = d1/2 = 15/2 mm
Since t<span>he ratio of the radii of two circles is 2:3, we have:
r1 : r2 = 2 : 3
which can also be expressed as:
</span>
![\frac{r1}{r2}= \frac{2}{3}](https://tex.z-dn.net/?f=%20%5Cfrac%7Br1%7D%7Br2%7D%3D%20%5Cfrac%7B2%7D%7B3%7D%20)
<span>
We know that r1 is 7.5, so let's implement it:
</span>
![\frac{7.5}{r2} = \frac{2}{3}](https://tex.z-dn.net/?f=%20%5Cfrac%7B7.5%7D%7Br2%7D%20%3D%20%5Cfrac%7B2%7D%7B3%7D%20)
Let's multiply both sides of the by 3r2:
![3r2* \frac{7.5}{r2} =3r2* \frac{2}{3}](https://tex.z-dn.net/?f=3r2%2A%20%5Cfrac%7B7.5%7D%7Br2%7D%20%3D3r2%2A%20%5Cfrac%7B2%7D%7B3%7D%20)
⇒
![22.5 = 2*r2](https://tex.z-dn.net/?f=22.5%20%3D%202%2Ar2)
⇒
Answer:
7
Step-by-step explanation:
1-10 is the answer to the question
Answer:
Option (c) is correct.
Step-by-step explanation:
Given equation is :
![s=\dfrac{a+b+c}{3}](https://tex.z-dn.net/?f=s%3D%5Cdfrac%7Ba%2Bb%2Bc%7D%7B3%7D)
The equation can be solved for a as follows :
Step 1.
Cross multiply the given equation
![3s=a+b+c](https://tex.z-dn.net/?f=3s%3Da%2Bb%2Bc)
Step 2.
Now subtract b on both sides
3s-b = a+b+c-b
3s-b = a+c
Step 3.
Subtract c on both sides
3s-b-c=a+c-c
⇒ a=3s-b-c
The statement that is true for Darpana is " In step 3, she needed to subtract c rather than divide".