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Finding the Fourth Proportional to 653.08, 901.20 and 391

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Solution

The fourth proportional to 653.08, 901.20 and 391 is: 539.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.08 : 901.20 = 391 : x
  2. Step 2: Convert to fraction form
    653.08/901.20 = 391/x
  3. Step 3: Cross multiply
    653.08x = 901.20 × 391
  4. Step 4: Simplify right side
    653.08x = 352,369.20
  5. Step 5: Solve for x
    x = 352,369.20/653.08
  6. Step 6: Final answer
    x = 539.55

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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.