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Finding the Fourth Proportional to 430.28, 645.30 and 308.18

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Solution

The fourth proportional to 430.28, 645.30 and 308.18 is: 462.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.28 : 645.30 = 308.18 : x
  2. Step 2: Convert to fraction form
    430.28/645.30 = 308.18/x
  3. Step 3: Cross multiply
    430.28x = 645.30 × 308.18
  4. Step 4: Simplify right side
    430.28x = 198,868.55
  5. Step 5: Solve for x
    x = 198,868.55/430.28
  6. Step 6: Final answer
    x = 462.18

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.