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Finding the Fourth Proportional to 97.85, 135.02 and 56.40

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Solution

The fourth proportional to 97.85, 135.02 and 56.40 is: 77.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    97.85 : 135.02 = 56.40 : x
  2. Step 2: Convert to fraction form
    97.85/135.02 = 56.40/x
  3. Step 3: Cross multiply
    97.85x = 135.02 × 56.40
  4. Step 4: Simplify right side
    97.85x = 7,615.13
  5. Step 5: Solve for x
    x = 7,615.13/97.85
  6. Step 6: Final answer
    x = 77.82

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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.