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Finding the Fourth Proportional to 520.40, 715.56 and 498.80

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Solution

The fourth proportional to 520.40, 715.56 and 498.80 is: 685.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.40 : 715.56 = 498.80 : x
  2. Step 2: Convert to fraction form
    520.40/715.56 = 498.80/x
  3. Step 3: Cross multiply
    520.40x = 715.56 × 498.80
  4. Step 4: Simplify right side
    520.40x = 356,921.33
  5. Step 5: Solve for x
    x = 356,921.33/520.40
  6. Step 6: Final answer
    x = 685.86

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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.