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Finding the Fourth Proportional to 499.32, 689.11 and 278.30

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Solution

The fourth proportional to 499.32, 689.11 and 278.30 is: 384.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.32 : 689.11 = 278.30 : x
  2. Step 2: Convert to fraction form
    499.32/689.11 = 278.30/x
  3. Step 3: Cross multiply
    499.32x = 689.11 × 278.30
  4. Step 4: Simplify right side
    499.32x = 191,780.34
  5. Step 5: Solve for x
    x = 191,780.34/499.32
  6. Step 6: Final answer
    x = 384.08

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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.