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Finding the Fourth Proportional to 628.92, 868.14 and 419.40

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Solution

The fourth proportional to 628.92, 868.14 and 419.40 is: 578.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.92 : 868.14 = 419.40 : x
  2. Step 2: Convert to fraction form
    628.92/868.14 = 419.40/x
  3. Step 3: Cross multiply
    628.92x = 868.14 × 419.40
  4. Step 4: Simplify right side
    628.92x = 364,097.92
  5. Step 5: Solve for x
    x = 364,097.92/628.92
  6. Step 6: Final answer
    x = 578.93

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1.5x scale

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.