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Finding the Fourth Proportional to 457.20, 630.72 and 309.87

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Solution

The fourth proportional to 457.20, 630.72 and 309.87 is: 427.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    457.20 : 630.72 = 309.87 : x
  2. Step 2: Convert to fraction form
    457.20/630.72 = 309.87/x
  3. Step 3: Cross multiply
    457.20x = 630.72 × 309.87
  4. Step 4: Simplify right side
    457.20x = 195,441.21
  5. Step 5: Solve for x
    x = 195,441.21/457.20
  6. Step 6: Final answer
    x = 427.47

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.