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Finding the Fourth Proportional to 412.70, 618.80 and 207.50

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Solution

The fourth proportional to 412.70, 618.80 and 207.50 is: 311.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.70 : 618.80 = 207.50 : x
  2. Step 2: Convert to fraction form
    412.70/618.80 = 207.50/x
  3. Step 3: Cross multiply
    412.70x = 618.80 × 207.50
  4. Step 4: Simplify right side
    412.70x = 128,396.87
  5. Step 5: Solve for x
    x = 128,396.87/412.70
  6. Step 6: Final answer
    x = 311.12

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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.