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Finding the Fourth Proportional to 427.77, 640.78 and 397.02

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Solution

The fourth proportional to 427.77, 640.78 and 397.02 is: 594.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.77 : 640.78 = 397.02 : x
  2. Step 2: Convert to fraction form
    427.77/640.78 = 397.02/x
  3. Step 3: Cross multiply
    427.77x = 640.78 × 397.02
  4. Step 4: Simplify right side
    427.77x = 254,402.48
  5. Step 5: Solve for x
    x = 254,402.48/427.77
  6. Step 6: Final answer
    x = 594.72

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.