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Finding the Fourth Proportional to 653.88, 901.86 and 391.80

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Solution

The fourth proportional to 653.88, 901.86 and 391.80 is: 540.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.88 : 901.86 = 391.80 : x
  2. Step 2: Convert to fraction form
    653.88/901.86 = 391.80/x
  3. Step 3: Cross multiply
    653.88x = 901.86 × 391.80
  4. Step 4: Simplify right side
    653.88x = 353,348.75
  5. Step 5: Solve for x
    x = 353,348.75/653.88
  6. Step 6: Final answer
    x = 540.39

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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.