Find the circumference of a circle whose diameter is
Q(i) 35 cm
(ii) 4.9 m. 

Answer

To find the circumference of a circle, we can use the formula:

\[ \text{Circumference} = \pi \times \text{Diameter} \]

Alternatively, if we know the radius, we can use:

\[ \text{Circumference} = 2 \pi r \]

Where:
- \(\pi\) is approximately \(3.14\) or \(\frac{22}{7}\)
- \(r\) is the radius of the circle

Now, let's solve the question step by step for both parts.

### Part (i): Diameter = 35 cm

**Step 1:** Identify the diameter.
- Given diameter \(D = 35 \, \text{cm}\)

**Step 2:** Calculate the circumference using the formula.
- Using the formula \(\text{Circumference} = \pi \times D\)
- Substitute \(\pi = \frac{22}{7}\) and \(D = 35 \, \text{cm}\)

\[ \text{Circumference} = \frac{22}{7} \times 35 \]

**Step 3:** Simplify the calculation.
- First, calculate \( \frac{22 \times 35}{7} \)
- \( 35 \div 7 = 5 \)
- Now, \( 22 \times 5 = 110 \)

So, the circumference is:

\[ \text{Circumference} = 110 \, \text{cm} \]

### Part (ii): Diameter = 4.9 m

**Step 1:** Identify the diameter.
- Given diameter \(D = 4.9 \, \text{m}\)

**Step 2:** Calculate the circumference using the formula.
- Using the formula \(\text{Circumference} = \pi \times D\)
- Substitute \(\pi = \frac{22}{7}\) and \(D = 4.9 \, \text{m}\)

\[ \text{Circumference} = \frac{22}{7} \times 4.9 \]

**Step 3:** Convert 4.9 to a fraction for easier calculation.
- \(4.9 = \frac{49}{10}\)

Now substitute:

\[ \text{Circumference} = \frac{22}{7} \times \frac{49}{10} \]

**Step 4:** Multiply the fractions.
- \( \frac{22 \times 49}{7 \times 10} \)

**Step 5:** Simplify the calculation.
- First, calculate \( 49 \div 7 = 7 \)
- Now, \( 22 \times 7 = 154 \)

So, we have:

\[ \text{Circumference} = \frac{154}{10} = 15.4 \, \text{m} \]

### Final Answers:
(i) Circumference = 110 cm
(ii) Circumference = 15.4 m