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Finding the Fourth Proportional to 421.65, 583.34 and 392.49

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Solution

The fourth proportional to 421.65, 583.34 and 392.49 is: 542.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.65 : 583.34 = 392.49 : x
  2. Step 2: Convert to fraction form
    421.65/583.34 = 392.49/x
  3. Step 3: Cross multiply
    421.65x = 583.34 × 392.49
  4. Step 4: Simplify right side
    421.65x = 228,953.15
  5. Step 5: Solve for x
    x = 228,953.15/421.65
  6. Step 6: Final answer
    x = 542.99

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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.