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Finding the Fourth Proportional to 680.07, 938.40 and 400.35

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Solution

The fourth proportional to 680.07, 938.40 and 400.35 is: 552.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.07 : 938.40 = 400.35 : x
  2. Step 2: Convert to fraction form
    680.07/938.40 = 400.35/x
  3. Step 3: Cross multiply
    680.07x = 938.40 × 400.35
  4. Step 4: Simplify right side
    680.07x = 375,688.44
  5. Step 5: Solve for x
    x = 375,688.44/680.07
  6. Step 6: Final answer
    x = 552.43

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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.