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The ratio of the outer and inner perimet...

The ratio of the outer and inner perimeters of a circular path is 23:22. If the path is 5 m wide, what is the diameter of the inner circle ? Also , find the area of path enclosed between the two circle?

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To solve the problem step by step, let's break it down: ### Step 1: Understand the given ratio The ratio of the outer perimeter (circumference) to the inner perimeter of the circular path is given as 23:22. ### Step 2: Set up the equations Let the radius of the inner circle be \( r_1 \) and the radius of the outer circle be \( r_2 \). The relationship based on the given ratio can be expressed as: \[ \frac{r_2}{r_1} = \frac{23}{22} \] This implies: \[ r_2 = \frac{23}{22} r_1 \] ### Step 3: Relate the radii to the width of the path The width of the circular path is given as 5 m. This means: \[ r_2 - r_1 = 5 \] ### Step 4: Substitute \( r_2 \) in terms of \( r_1 \) Substituting the expression for \( r_2 \) from Step 2 into the equation from Step 3: \[ \frac{23}{22} r_1 - r_1 = 5 \] ### Step 5: Solve for \( r_1 \) Combine the terms: \[ \left(\frac{23}{22} - 1\right) r_1 = 5 \] \[ \left(\frac{23 - 22}{22}\right) r_1 = 5 \] \[ \frac{1}{22} r_1 = 5 \] Multiplying both sides by 22: \[ r_1 = 5 \times 22 = 110 \text{ m} \] ### Step 6: Find the diameter of the inner circle The diameter \( d_1 \) of the inner circle is given by: \[ d_1 = 2 \times r_1 = 2 \times 110 = 220 \text{ m} \] ### Step 7: Find the area of the path enclosed between the two circles The area of the path is the difference between the area of the outer circle and the inner circle: \[ \text{Area} = \pi r_2^2 - \pi r_1^2 \] Factoring out \( \pi \): \[ \text{Area} = \pi (r_2^2 - r_1^2) \] ### Step 8: Calculate \( r_2 \) Using the relationship \( r_2 = \frac{23}{22} r_1 \): \[ r_2 = \frac{23}{22} \times 110 = 115 \text{ m} \] ### Step 9: Substitute \( r_2 \) and \( r_1 \) into the area formula Now substitute \( r_1 \) and \( r_2 \): \[ \text{Area} = \pi (115^2 - 110^2) \] Calculating \( 115^2 \) and \( 110^2 \): \[ 115^2 = 13225, \quad 110^2 = 12100 \] Thus, \[ \text{Area} = \pi (13225 - 12100) = \pi \times 1125 \] ### Step 10: Calculate the area using \( \pi \approx \frac{22}{7} \) \[ \text{Area} = \frac{22}{7} \times 1125 = \frac{24750}{7} \approx 3535.71 \text{ m}^2 \] ### Final Answers: - The diameter of the inner circle is **220 m**. - The area of the path enclosed between the two circles is approximately **3535.71 m²**. ---
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