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Finding the Fourth Proportional to 647.42, 893.30 and 381.78

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Solution

The fourth proportional to 647.42, 893.30 and 381.78 is: 526.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.42 : 893.30 = 381.78 : x
  2. Step 2: Convert to fraction form
    647.42/893.30 = 381.78/x
  3. Step 3: Cross multiply
    647.42x = 893.30 × 381.78
  4. Step 4: Simplify right side
    647.42x = 341,044.07
  5. Step 5: Solve for x
    x = 341,044.07/647.42
  6. Step 6: Final answer
    x = 526.77

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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.