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Finding the Fourth Proportional to 654.68, 979.55 and 390.16

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Solution

The fourth proportional to 654.68, 979.55 and 390.16 is: 583.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.68 : 979.55 = 390.16 : x
  2. Step 2: Convert to fraction form
    654.68/979.55 = 390.16/x
  3. Step 3: Cross multiply
    654.68x = 979.55 × 390.16
  4. Step 4: Simplify right side
    654.68x = 382,179.75
  5. Step 5: Solve for x
    x = 382,179.75/654.68
  6. Step 6: Final answer
    x = 583.76

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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.