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Finding the Fourth Proportional to 680.15, 938.21 and 515.00

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Solution

The fourth proportional to 680.15, 938.21 and 515.00 is: 710.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.15 : 938.21 = 515.00 : x
  2. Step 2: Convert to fraction form
    680.15/938.21 = 515.00/x
  3. Step 3: Cross multiply
    680.15x = 938.21 × 515.00
  4. Step 4: Simplify right side
    680.15x = 483,177.92
  5. Step 5: Solve for x
    x = 483,177.92/680.15
  6. Step 6: Final answer
    x = 710.40

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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.