Суреттегі бір-бірлеріне тең болатын кіші дөңгелектердің әрқайсының радиусы 7 см тең болса, үлкен шеңбердің диаметрі мен радиусын есептеңіз.

Translation: If the radius of each of the small circles in the picture that are equal to each other is 7 cm, calculate the diameter and radius of the large circle.

Let's denote:

• r - radius of each small circle, which is 7 cm.
• R - radius of the large circle.
• D - diameter of the large circle.

From the picture, we can see that the diameter of the large circle is equal to the sum of the diameters of four small circles aligned along the red line.

So, the diameter of the large circle can be calculated as follows:

$$D = 4 cdot (2r) = 8r$$

Substituting the value of r:

$$D = 8 cdot 7 = 56$$ cm

Now, let's calculate the radius of the large circle:

$$R = \frac{D}{2} = \frac{56}{2} = 28$$ cm

Answer: The diameter of the large circle is 56 cm, and its radius is 28 cm.