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Finding the Fourth Proportional to 498.45, 688.12 and 312.05

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Solution

The fourth proportional to 498.45, 688.12 and 312.05 is: 430.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.45 : 688.12 = 312.05 : x
  2. Step 2: Convert to fraction form
    498.45/688.12 = 312.05/x
  3. Step 3: Cross multiply
    498.45x = 688.12 × 312.05
  4. Step 4: Simplify right side
    498.45x = 214,727.85
  5. Step 5: Solve for x
    x = 214,727.85/498.45
  6. Step 6: Final answer
    x = 430.79

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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.