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Finding the Fourth Proportional to 500.12, 690.20 and 279.11

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Solution

The fourth proportional to 500.12, 690.20 and 279.11 is: 385.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.12 : 690.20 = 279.11 : x
  2. Step 2: Convert to fraction form
    500.12/690.20 = 279.11/x
  3. Step 3: Cross multiply
    500.12x = 690.20 × 279.11
  4. Step 4: Simplify right side
    500.12x = 192,643.10
  5. Step 5: Solve for x
    x = 192,643.10/500.12
  6. Step 6: Final answer
    x = 385.19

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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.