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Finding the Fourth Proportional to 690.32, 1,035.18 and 279.32

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Solution

The fourth proportional to 690.32, 1,035.18 and 279.32 is: 418.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.32 : 1,035.18 = 279.32 : x
  2. Step 2: Convert to fraction form
    690.32/1,035.18 = 279.32/x
  3. Step 3: Cross multiply
    690.32x = 1,035.18 × 279.32
  4. Step 4: Simplify right side
    690.32x = 289,141.30
  5. Step 5: Solve for x
    x = 289,141.30/690.32
  6. Step 6: Final answer
    x = 418.85

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.