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Finding the Fourth Proportional to 653.40, 978.75 and 392.58

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Solution

The fourth proportional to 653.40, 978.75 and 392.58 is: 588.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.40 : 978.75 = 392.58 : x
  2. Step 2: Convert to fraction form
    653.40/978.75 = 392.58/x
  3. Step 3: Cross multiply
    653.40x = 978.75 × 392.58
  4. Step 4: Simplify right side
    653.40x = 384,237.68
  5. Step 5: Solve for x
    x = 384,237.68/653.40
  6. Step 6: Final answer
    x = 588.06

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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.