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Finding the Fourth Proportional to 1,109.31, 1,663.85 and 378.80

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Solution

The fourth proportional to 1,109.31, 1,663.85 and 378.80 is: 568.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,109.31 : 1,663.85 = 378.80 : x
  2. Step 2: Convert to fraction form
    1,109.31/1,663.85 = 378.80/x
  3. Step 3: Cross multiply
    1,109.31x = 1,663.85 × 378.80
  4. Step 4: Simplify right side
    1,109.31x = 630,256.17
  5. Step 5: Solve for x
    x = 630,256.17/1,109.31
  6. Step 6: Final answer
    x = 568.15

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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.