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Finding the Fourth Proportional to 530.40, 688.80 and 530.40

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Solution

The fourth proportional to 530.40, 688.80 and 530.40 is: 688.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    530.40 : 688.80 = 530.40 : x
  2. Step 2: Convert to fraction form
    530.40/688.80 = 530.40/x
  3. Step 3: Cross multiply
    530.40x = 688.80 × 530.40
  4. Step 4: Simplify right side
    530.40x = 365,339.52
  5. Step 5: Solve for x
    x = 365,339.52/530.40
  6. Step 6: Final answer
    x = 688.80

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Why These Related Problems?

These problems maintain the same ratio (1.30) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.