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Finding the Fourth Proportional to 419.99, 630.05 and 386.10

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Solution

The fourth proportional to 419.99, 630.05 and 386.10 is: 579.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.99 : 630.05 = 386.10 : x
  2. Step 2: Convert to fraction form
    419.99/630.05 = 386.10/x
  3. Step 3: Cross multiply
    419.99x = 630.05 × 386.10
  4. Step 4: Simplify right side
    419.99x = 243,260.37
  5. Step 5: Solve for x
    x = 243,260.37/419.99
  6. Step 6: Final answer
    x = 579.21

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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.