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Finding the Fourth Proportional to 499.15, 688.80 and 278.12

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Solution

The fourth proportional to 499.15, 688.80 and 278.12 is: 383.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.15 : 688.80 = 278.12 : x
  2. Step 2: Convert to fraction form
    499.15/688.80 = 278.12/x
  3. Step 3: Cross multiply
    499.15x = 688.80 × 278.12
  4. Step 4: Simplify right side
    499.15x = 191,569.06
  5. Step 5: Solve for x
    x = 191,569.06/499.15
  6. Step 6: Final answer
    x = 383.79

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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.