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Finding the Fourth Proportional to 680.12, 938.52 and 400.40

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Solution

The fourth proportional to 680.12, 938.52 and 400.40 is: 552.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.12 : 938.52 = 400.40 : x
  2. Step 2: Convert to fraction form
    680.12/938.52 = 400.40/x
  3. Step 3: Cross multiply
    680.12x = 938.52 × 400.40
  4. Step 4: Simplify right side
    680.12x = 375,783.41
  5. Step 5: Solve for x
    x = 375,783.41/680.12
  6. Step 6: Final answer
    x = 552.53

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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.