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Finding the Fourth Proportional to 761.85, 1,050.78 and 478.35

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Solution

The fourth proportional to 761.85, 1,050.78 and 478.35 is: 659.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    761.85 : 1,050.78 = 478.35 : x
  2. Step 2: Convert to fraction form
    761.85/1,050.78 = 478.35/x
  3. Step 3: Cross multiply
    761.85x = 1,050.78 × 478.35
  4. Step 4: Simplify right side
    761.85x = 502,640.61
  5. Step 5: Solve for x
    x = 502,640.61/761.85
  6. Step 6: Final answer
    x = 659.76

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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.