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Finding the Fourth Proportional to 498.89, 688.20 and 312.34

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Solution

The fourth proportional to 498.89, 688.20 and 312.34 is: 430.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    498.89 : 688.20 = 312.34 : x
  2. Step 2: Convert to fraction form
    498.89/688.20 = 312.34/x
  3. Step 3: Cross multiply
    498.89x = 688.20 × 312.34
  4. Step 4: Simplify right side
    498.89x = 214,954.48
  5. Step 5: Solve for x
    x = 214,954.48/498.89
  6. Step 6: Final answer
    x = 430.86

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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.