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Finding the Fourth Proportional to 663.80, 916.19 and 439.78

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Solution

The fourth proportional to 663.80, 916.19 and 439.78 is: 607.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.80 : 916.19 = 439.78 : x
  2. Step 2: Convert to fraction form
    663.80/916.19 = 439.78/x
  3. Step 3: Cross multiply
    663.80x = 916.19 × 439.78
  4. Step 4: Simplify right side
    663.80x = 402,923.39
  5. Step 5: Solve for x
    x = 402,923.39/663.80
  6. Step 6: Final answer
    x = 607.00

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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.