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Finding the Fourth Proportional to 500.55, 690.78 and 279.58

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Solution

The fourth proportional to 500.55, 690.78 and 279.58 is: 385.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.55 : 690.78 = 279.58 : x
  2. Step 2: Convert to fraction form
    500.55/690.78 = 279.58/x
  3. Step 3: Cross multiply
    500.55x = 690.78 × 279.58
  4. Step 4: Simplify right side
    500.55x = 193,128.27
  5. Step 5: Solve for x
    x = 193,128.27/500.55
  6. Step 6: Final answer
    x = 385.84

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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.