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Finding the Fourth Proportional to 680.10, 938.45 and 400.45

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Solution

The fourth proportional to 680.10, 938.45 and 400.45 is: 552.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.10 : 938.45 = 400.45 : x
  2. Step 2: Convert to fraction form
    680.10/938.45 = 400.45/x
  3. Step 3: Cross multiply
    680.10x = 938.45 × 400.45
  4. Step 4: Simplify right side
    680.10x = 375,802.30
  5. Step 5: Solve for x
    x = 375,802.30/680.10
  6. Step 6: Final answer
    x = 552.57

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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.