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Finding the Fourth Proportional to 500.07, 690.05 and 279.05

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Solution

The fourth proportional to 500.07, 690.05 and 279.05 is: 385.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.07 : 690.05 = 279.05 : x
  2. Step 2: Convert to fraction form
    500.07/690.05 = 279.05/x
  3. Step 3: Cross multiply
    500.07x = 690.05 × 279.05
  4. Step 4: Simplify right side
    500.07x = 192,555.70
  5. Step 5: Solve for x
    x = 192,555.70/500.07
  6. Step 6: Final answer
    x = 385.05

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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.