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Finding the Fourth Proportional to 653.20, 901.40 and 391.30

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Solution

The fourth proportional to 653.20, 901.40 and 391.30 is: 539.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.20 : 901.40 = 391.30 : x
  2. Step 2: Convert to fraction form
    653.20/901.40 = 391.30/x
  3. Step 3: Cross multiply
    653.20x = 901.40 × 391.30
  4. Step 4: Simplify right side
    653.20x = 352,717.82
  5. Step 5: Solve for x
    x = 352,717.82/653.20
  6. Step 6: Final answer
    x = 539.98

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.