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Finding the Fourth Proportional to 672.80, 928.50 and 393.12

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Solution

The fourth proportional to 672.80, 928.50 and 393.12 is: 542.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    672.80 : 928.50 = 393.12 : x
  2. Step 2: Convert to fraction form
    672.80/928.50 = 393.12/x
  3. Step 3: Cross multiply
    672.80x = 928.50 × 393.12
  4. Step 4: Simplify right side
    672.80x = 365,011.92
  5. Step 5: Solve for x
    x = 365,011.92/672.80
  6. Step 6: Final answer
    x = 542.53

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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.