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Finding the Fourth Proportional to 781.36, 1,077.48 and 470.80

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Solution

The fourth proportional to 781.36, 1,077.48 and 470.80 is: 649.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    781.36 : 1,077.48 = 470.80 : x
  2. Step 2: Convert to fraction form
    781.36/1,077.48 = 470.80/x
  3. Step 3: Cross multiply
    781.36x = 1,077.48 × 470.80
  4. Step 4: Simplify right side
    781.36x = 507,277.58
  5. Step 5: Solve for x
    x = 507,277.58/781.36
  6. Step 6: Final answer
    x = 649.22

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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.