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Finding the Fourth Proportional to 412.80, 618.87 and 207.45

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Solution

The fourth proportional to 412.80, 618.87 and 207.45 is: 311.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.80 : 618.87 = 207.45 : x
  2. Step 2: Convert to fraction form
    412.80/618.87 = 207.45/x
  3. Step 3: Cross multiply
    412.80x = 618.87 × 207.45
  4. Step 4: Simplify right side
    412.80x = 128,384.58
  5. Step 5: Solve for x
    x = 128,384.58/412.80
  6. Step 6: Final answer
    x = 311.01

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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.