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Finding the Fourth Proportional to 499.30, 689.05 and 278.25

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Solution

The fourth proportional to 499.30, 689.05 and 278.25 is: 383.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.30 : 689.05 = 278.25 : x
  2. Step 2: Convert to fraction form
    499.30/689.05 = 278.25/x
  3. Step 3: Cross multiply
    499.30x = 689.05 × 278.25
  4. Step 4: Simplify right side
    499.30x = 191,727.74
  5. Step 5: Solve for x
    x = 191,727.74/499.30
  6. Step 6: Final answer
    x = 383.99

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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.