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Finding the Fourth Proportional to 487.40, 727.99 and 419.12

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Solution

The fourth proportional to 487.40, 727.99 and 419.12 is: 626.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.40 : 727.99 = 419.12 : x
  2. Step 2: Convert to fraction form
    487.40/727.99 = 419.12/x
  3. Step 3: Cross multiply
    487.40x = 727.99 × 419.12
  4. Step 4: Simplify right side
    487.40x = 305,115.17
  5. Step 5: Solve for x
    x = 305,115.17/487.40
  6. Step 6: Final answer
    x = 626.01

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.