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Finding the Fourth Proportional to 499.32, 688.78 and 315

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Solution

The fourth proportional to 499.32, 688.78 and 315 is: 434.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.32 : 688.78 = 315 : x
  2. Step 2: Convert to fraction form
    499.32/688.78 = 315/x
  3. Step 3: Cross multiply
    499.32x = 688.78 × 315
  4. Step 4: Simplify right side
    499.32x = 216,965.70
  5. Step 5: Solve for x
    x = 216,965.70/499.32
  6. Step 6: Final answer
    x = 434.52

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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.