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Finding the Fourth Proportional to 628.79, 867.65 and 392.74

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Solution

The fourth proportional to 628.79, 867.65 and 392.74 is: 541.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.79 : 867.65 = 392.74 : x
  2. Step 2: Convert to fraction form
    628.79/867.65 = 392.74/x
  3. Step 3: Cross multiply
    628.79x = 867.65 × 392.74
  4. Step 4: Simplify right side
    628.79x = 340,756.73
  5. Step 5: Solve for x
    x = 340,756.73/628.79
  6. Step 6: Final answer
    x = 541.93

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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.