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Finding the Fourth Proportional to 419.99, 630.18 and 257.99

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Solution

The fourth proportional to 419.99, 630.18 and 257.99 is: 387.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.99 : 630.18 = 257.99 : x
  2. Step 2: Convert to fraction form
    419.99/630.18 = 257.99/x
  3. Step 3: Cross multiply
    419.99x = 630.18 × 257.99
  4. Step 4: Simplify right side
    419.99x = 162,576.99
  5. Step 5: Solve for x
    x = 162,576.99/419.99
  6. Step 6: Final answer
    x = 387.10

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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.