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Finding the Fourth Proportional to 653.11, 901.12 and 390.94

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Solution

The fourth proportional to 653.11, 901.12 and 390.94 is: 539.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.11 : 901.12 = 390.94 : x
  2. Step 2: Convert to fraction form
    653.11/901.12 = 390.94/x
  3. Step 3: Cross multiply
    653.11x = 901.12 × 390.94
  4. Step 4: Simplify right side
    653.11x = 352,278.37
  5. Step 5: Solve for x
    x = 352,278.37/653.11
  6. Step 6: Final answer
    x = 539.39

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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.