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Finding the Fourth Proportional to 815.80, 1,125.76 and 479.66

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Solution

The fourth proportional to 815.80, 1,125.76 and 479.66 is: 661.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    815.80 : 1,125.76 = 479.66 : x
  2. Step 2: Convert to fraction form
    815.80/1,125.76 = 479.66/x
  3. Step 3: Cross multiply
    815.80x = 1,125.76 × 479.66
  4. Step 4: Simplify right side
    815.80x = 539,982.04
  5. Step 5: Solve for x
    x = 539,982.04/815.80
  6. Step 6: Final answer
    x = 661.90

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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.