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Finding the Fourth Proportional to 680.30, 938.75 and 381.53

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Solution

The fourth proportional to 680.30, 938.75 and 381.53 is: 526.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.30 : 938.75 = 381.53 : x
  2. Step 2: Convert to fraction form
    680.30/938.75 = 381.53/x
  3. Step 3: Cross multiply
    680.30x = 938.75 × 381.53
  4. Step 4: Simplify right side
    680.30x = 358,156.59
  5. Step 5: Solve for x
    x = 358,156.59/680.30
  6. Step 6: Final answer
    x = 526.47

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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.