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Finding the Fourth Proportional to 780.96, 1,077.92 and 470.72

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Solution

The fourth proportional to 780.96, 1,077.92 and 470.72 is: 649.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.96 : 1,077.92 = 470.72 : x
  2. Step 2: Convert to fraction form
    780.96/1,077.92 = 470.72/x
  3. Step 3: Cross multiply
    780.96x = 1,077.92 × 470.72
  4. Step 4: Simplify right side
    780.96x = 507,398.50
  5. Step 5: Solve for x
    x = 507,398.50/780.96
  6. Step 6: Final answer
    x = 649.71

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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.