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Finding the Fourth Proportional to 718.87, 991.69 and 470.20

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Solution

The fourth proportional to 718.87, 991.69 and 470.20 is: 648.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    718.87 : 991.69 = 470.20 : x
  2. Step 2: Convert to fraction form
    718.87/991.69 = 470.20/x
  3. Step 3: Cross multiply
    718.87x = 991.69 × 470.20
  4. Step 4: Simplify right side
    718.87x = 466,290.29
  5. Step 5: Solve for x
    x = 466,290.29/718.87
  6. Step 6: Final answer
    x = 648.64

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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.