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Finding the Fourth Proportional to 500.80, 750.40 and 419.20

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Solution

The fourth proportional to 500.80, 750.40 and 419.20 is: 628.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.80 : 750.40 = 419.20 : x
  2. Step 2: Convert to fraction form
    500.80/750.40 = 419.20/x
  3. Step 3: Cross multiply
    500.80x = 750.40 × 419.20
  4. Step 4: Simplify right side
    500.80x = 314,567.68
  5. Step 5: Solve for x
    x = 314,567.68/500.80
  6. Step 6: Final answer
    x = 628.13

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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.