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Finding the Fourth Proportional to 500.60, 690.80 and 279.50

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Solution

The fourth proportional to 500.60, 690.80 and 279.50 is: 385.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.60 : 690.80 = 279.50 : x
  2. Step 2: Convert to fraction form
    500.60/690.80 = 279.50/x
  3. Step 3: Cross multiply
    500.60x = 690.80 × 279.50
  4. Step 4: Simplify right side
    500.60x = 193,077.20
  5. Step 5: Solve for x
    x = 193,077.20/500.60
  6. Step 6: Final answer
    x = 385.70

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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.